Central Person Register Research Articles

Age-related maculopathy: A risk indicator for poorer survival in women: The Copenhagen City Eye Study

To examine patient survival in age-related maculopathy in a 14-year follow-up study. Population-based 14-year cohort study. Nine hundred forty-six residents, aged 60 to 80 years, living in the Osterbro district of Copenhagen, Denmark, participated in the first examination conducted from 1986 to 1988. These participants were followed until death or until May 1, 2002, whichever came first. Participants underwent an extensive ophthalmologic examination at Rigshospitalet, the National University Hospital of Copenhagen. Standardized protocols for physical examination, blood samples, and data from the National Central Person Register, the National Death Register, and the National Patient Register were used. Mortality and age-related maculopathy. By May 1, 2002, 60.9% (577 of 946) of the participants of the baseline study cohort had died. The adjusted 14-year cumulative mortality hazard ratio for subjects with early and late age-related maculopathy at baseline was 1.26 (95% confidence interval [CI], 1.06-1.51). We identified a strong correlation between mortality and age-related maculopathy among women (relative risk, 1.59; 95% CI, 1.23-2.07) but not among men. When adjusting for survival-related factors, age-related maculopathy is a significant risk indicator for poorer survival in women and may be a marker of underlying serious systemic factors or aging processes specific to women.

Use of Oral Contraceptives, Alcohol, and Risk for Invasive Breast Cancer

Abstract The aim of our study was to examine how the use of oral contraceptives (OCs) interact with alcohol on breast cancer risk within the large prospective follow-up study, Norwegian Women and Cancer Study. Between 1991 and 1997, women aged 30 to 70 years were drawn at random from the central person register and mailed an invitation. Follow-up information was collected throughout 2001 by linkage to national registries. Only women (n = 86,948) with complete information on alcohol consumption and duration of OC use were included in the present analysis. A total of 1,130 invasive breast cancers were diagnosed during 618,638 person-years of follow-up. Consumption of ≥10.0 g/d alcohol was associated with a breast cancer relative risk (95% confidence interval) of 1.69 (1.32-2.15), consistent with a linear relationship (P for trend < 0.0001). Among alcohol consumers, an excess risk of breast cancer was observed for total duration of OC use only among women who consumed <5 g/d alcohol (P for trend = 0.0009). We observed a negative interaction between duration of OC use and alcohol consumption effects (P for interaction = 0.01). After stratification on menopausal status, the association between high alcohol intake and breast cancer was more prominent among postmenopausal women than among premenopausal women (P for heterogeneity = 0.01). No interaction between alcohol and duration of OC use were significant after stratification on menopausal status. Our findings in conjunction with biological data imply that alcohol and OCs have antagonistic effects on breast cancer risk through a common pathway. Whether the interactive effect differs according to menopausal status remains unclear and needs further investigations.

Inflammatory Bowel Diseases, 5-Aminosalicylic Acid and Sulfasalazine Treatment and Risk of Acute Pancreatitis: A Population-Based Case-Control Study

Patients with inflammatory bowel diseases are suggested to have an increased risk of acute pancreatitis. Although azathioprine and glucocorticoids are risk factors for acute pancreatitis, the relation is poorly understood, in particular the role of 5-aminosalicylic acid and sulfasalazine treatment. To clarify these relations, we conducted a population-based case-control study. We identified 1,590 incident cases of acute pancreatitis from the Hospital Discharge Registry of the North Jutland County of Denmark from 1991 to 2002, and selected 10 controls per case (N = 15,913) from the Central Personal Registry, matched by age and gender. Among cases and controls, we identified patients with inflammatory bowel diseases. Data on drug use were extracted from a Pharmaco-epidemiological Prescription Database. Adjusted odds ratios for acute pancreatitis in patients with Crohn's disease and ulcerative colitis were 3.7 (95% confidence interval (CI), 1.9-7.6) and 1.5 (95% CI, 0.7-3.6), respectively. In all patients treated with 5-aminosalicylic acid and sulfasalazine the adjusted odds ratios for acute pancreatitis were 0.7 (95% CI, 0.4-2.2) and 1.5 (95% CI, 0.4-5.2), respectively. Restricted to patients with inflammatory bowel diseases only, the adjusted odds ratios for acute pancreatitis in patients exposed to 5-aminosalicylic acid and sulfasalazine were 0.7 (95% CI, 0.1-3.8) and 0.6 (95% CI, 0.1-6.7), respectively. We found a nearly four-fold increased risk of acute pancreatitis in patients with Crohn's disease and a 1.5-fold increased risk for ulcerative colitis. In patients with inflammatory bowel diseases, the use of 5-aminosalicylic acid or sulfasalazine was not associated with increased risk of acute pancreatitis.

Hip fracture risk in statin users--a population-based Danish case-control study.

Based on animal studies, statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) have been suggested as potential agents in the treatment of osteoporosis. In some epidemiological studies, statins have been associated with a reduced fracture risk. Our objective was to examine associations between statin treatment and risk of hip fracture in a population-based case-control study. A total of 6660 subjects with hip fracture and 33,274 gender- and age-matched population controls were identified from 1 January 1994 to 31 December 2001 using the Hospital Patient Register in North Jutland County, Denmark, and the Danish Central Personal Registry, respectively. Data on redeemed prescriptions for statins within the last 5 years before the index date were retrieved from a population-based prescription database. We used conditional logistic regression to estimate odds ratios (OR) for hip fracture according to use of statin prescriptions adjusted for potential confounding factors, i.e. gender, other diseases, and use of other drugs known to affect bone metabolism and fracture risk. After adjustment for potential confounders, statin treatment was associated with a reduced risk of hip fracture (OR=0.68; 95% confidence interval: 0.50-0.93) for those who had redeemed more than three prescriptions for a statin drug. We found that risk of hip fracture decreased with the number of statin prescriptions. Stratified analyses on gender and age did not reveal any major differences between men and women or among different age groups on the estimates between use of statins and hip fracture risk. Our findings support an association between statin treatment and a reduced hip fracture risk. However, it is unclear whether this association is causal.

External validity in a population-based national prospective study--the Norwegian Women and Cancer Study (NOWAC).

'The Norwegian Women and Cancer Study' (NOWAC) was created as a national population-based cohort study by taking advantage of the existing population registers in Norway. Thus, the women in the NOWAC study should be representative for the entire female population in the corresponding age-groups. The aim of this paper was to study the external validity of the cohort as a necessary premise for the estimation of population attributable risk. Between 1991 and 1997 women were sampled randomly from the national Central person registry in Norway. A total of 179,388 women were invited, of whom 102,443 can be included in the forthcoming follow-up analysis. The response-rates were around 60% in the age-groups 30-34 years till 55-59 years, while 44.7% responded among those aged 65-70 years. Information was collected by postal questionnaires. Follow-up information was based on linkage to national end-point registers with use of the unique national identification number given all Norwegians. Validation of the information on parity and education by linkage to national registers showed only minor differences for these factors between the responders and the total sample of women. A postal survey among non-responders indicated that the most important reasons for not returning the questionnaire were lack of time and concern about privacy. The results showed no differences in life-style factors between the original responders and the non-responders. No significant differences were found between the observed incidence rates for all cancer sites or cancer of the breast compared with national figures for the year 1999. The analysis revealed no major source of selection bias that could seriously invalidate the estimation of population attributable risk.

Corticosteroid use and risk of hip fracture: a population-based case-control study in Denmark.

To examine the association between cumulative CS dose and risk of hip fracture. Population-based case-control design. A total of 6660 subjects with hip fracture and 33,272 age-matched population controls were identified using the County Hospital Discharge Registry in North Jutland County, Denmark and the Danish Central Personal Registry, respectively. Data on redeemed prescriptions for CS within the last 5 years before the index date were retrieved from a population-based prescription database, and recalculated to prednisolone equivalents. Cases and controls were categorized according to cumulative CS dose: (i) no use; (ii) <130 mg (e.g. equivalent to 30 mg of prednisolone for 4 days given for an acute exacerbation of asthma); (iii) 130-499 mg (e.g. equivalent to a short course of prednisolone of 450 mg for acute asthma); (iv) 500-1499 mg (e.g. equivalent to 7.5 mg prednisolone daily for 6 months or 800 microg day(-1) of inhaled budesonide for 1 year); and (v) > or =1500 mg (e.g. equivalent to >4.1 mg day(-1) for 1 year, a long-term high dose). Data were analysed using conditional logistic regression adjusted for potential confounders including gender, redeemed prescriptions for hormone replacement therapy, antiosteoporotic, anxiolytic, antipsychotic and antidepressant drugs. Compared with never users, an increased risk of hip fracture was found for CS users, with increasing cumulative doses of any type of CS use during the preceding 5 years [adjusted odds ratio (OR)=0.96, 95% confidence interval (CI)=0.89-1.04] for <130 mg prednisolone; OR=1.17 (CI=1.01-1.35) for 130-499 mg; OR=1.36 (CI=1.19-1.56) for 500-1499 mg; and OR=1.65 (CI=1.43-1.92) for > or =1500 mg. An increased risk was also found when the study population was stratified according to gender, age and type of CS (systemic or topical). Even a limited daily dose of CS (more than an average dose of approximately 71 microg prednisolone per day) was associated with an increased risk of hip fracture.

Epidemiology of chronic non-malignant pain in Denmark

A series of health surveys are conducted every sixth to seventh year in Denmark. In the most recent survey of 2000, a national random sample (>16 years) was drawn from the Danish Central Personal Register. Out of the original sample 12,333 (74%) were interviewed and of these 10,066 returned a completed questionnaire (SF-36). The present study includes only those who both took part in the interview and the postal questionnaire. Cancer patients were excluded. Persons suffering from chronic pain (PG) were identified through the question ‘Do you have chronic/long lasting pain lasting 6 months or more’? An overall chronic pain prevalence of 19% was found −16% for men and 21% for women. Prevalence of chronic pain increased with increasing age. Persons ≥67 years had 3.9 higher odds of suffering from chronic pain than persons in the age group 16–24 years. Compared with married persons, divorced or separated persons had 1.5 higher odds of chronic pain. Odds for chronic pain were 1.9 higher among those with an education of less than 10 years compared with individuals with an education of 13 years or more. During a 14-day period reporters of chronic pain had an average of 0.8 days (range 0–10) lost due to illness compared with an average of 0.4 days (range 0–10) for the control group (CG) (Odds Ratio (OR)) 2.0). Persons with a job which required high physical strain were more likely to report chronic pain compared with those with a sedentary job (OR 2.2). The odds of quitting one's job because of ill health were seven times higher among people belonging to the PG. A strong association between chronic pain and poor self-rated health was also demonstrated. The PG had twice as many contacts with various health professionals compared with the CG, and the health care system was, on average, utilised 25% more (overall contacts) by the PG than by the general population. Among the persons in the PG, 33% were not satisfied with the examinations carried out in connection with their pain condition and 40% were not satisfied with the treatment offered. Nearly 130,000 adults, corresponding to 3% of the Danish population, use opioids on a regular basis. Opioids are used by 12% of the PG.

Risk of acute pancreatitis in users of azathioprine: a population-based case-control study.

Azathioprine has been linked to subsequent acute pancreatitis in several case reports and small case series. We examined the risk for acute pancreatitis in users of azathioprine in North Jutland County, Denmark, with about 490,000 inhabitants. We identified patients with incident cases of acute pancreatitis from the Hospital Discharge Registry of the county from 1991-2000, and selected 10 controls per case, matched by age and sex, from the Central Personal Registry using incidence density sampling technique. All prescriptions of azathioprine within 90 days before admission were likewise collected from the population-based North Jutland Prescription Database. Data on potential confounders were extracted from registries. We used conditional logistic regression to adjust for confounding. A total of 1,388 patients and 13,836 controls were included in the study. We found that 1,317 persons in the entire population redeemed a total of 15,811 prescriptions of azathioprine in the county. The incidence rate for acute pancreatitis among all users of azathioprine was one per 659 treatment year. The crude OR of having redeemed prescriptions for azathioprine within 90 days before admission for acute pancreatitis was 7.5 (95% CI = 2.6-21.6). After adjustment for gallstone disease, alcohol-related diseases, inflammatory bowel disease, and use of glucocorticoids, the OR increased to 8.4 (95% CI = 2.4-29.4). The population-attributable risk, which measures the proportion of all cases of pancreatitis that are attributable to the use of azathioprine in our study population, was 0.4%. There was a substantially increased relative risk of acute pancreatitis in users of azathioprine.

Risk of acute pancreatitis in users of azathioprine: a population-based case–control study

Objective Azathioprine has been linked to subsequent acute pancreatitis in several case reports and small case series. We examined the risk for acute pancreatitis in users of azathioprine in North Jutland County, Denmark, with about 490,000 inhabitants. Methods We identified patients with incident cases of acute pancreatitis from the Hospital Discharge Registry of the county from 1991–2000, and selected 10 controls per case, matched by age and sex, from the Central Personal Registry using incidence density sampling technique. All prescriptions of azathioprine within 90 days before admission were likewise collected from the population-based North Jutland Prescription Database. Data on potential confounders were extracted from registries. We used conditional logistic regression to adjust for confounding. Results A total of 1,388 patients and 13,836 controls were included in the study. We found that 1,317 persons in the entire population redeemed a total of 15,811 prescriptions of azathioprine in the county. The incidence rate for acute pancreatitis among all users of azathioprine was one per 659 treatment year. The crude OR of having redeemed prescriptions for azathioprine within 90 days before admission for acute pancreatitis was 7.5 (95% CI = 2.6–21.6). After adjustment for gallstone disease, alcohol-related diseases, inflammatory bowel disease, and use of glucocorticoids, the OR increased to 8.4 (95% CI = 2.4–29.4). The population-attributable risk, which measures the proportion of all cases of pancreatitis that are attributable to the use of azathioprine in our study population, was 0.4%. Conclusions There was a substantially increased relative risk of acute pancreatitis in users of azathioprine.

Breast cancer and specific types of oral contraceptives: a large Norwegian cohort study.

The aim of our study was to examine the risk of breast cancer according to specific types of estrogens and progestagens in oral contraceptives (OCs) based on the prospective Norwegian Women and Cancer study (NOWAC). Between 1991-97 women aged 30-70 years were drawn at random from the central person register and mailed an invitation and a questionnaire. Women (102,443) were enrolled with follow-up information collected throughout 1999 by linkage with national registries of cancer, mortality and emigration based on the unique national identification number. Among the 96,362 women included in the present analysis 851 invasive breast cancer were diagnosed. The adjusted risk of breast cancer increased with 25% for ever use of OCs and the risk increased with increasing duration of use (test for trend: p = 0.007). No association between time since last use and breast cancer risk was found after stratification on duration of use. Positive trend was still found for total duration of use among women who used OCs more than 5 years ago. Second generation of OCs had an increased risk with increasing duration of use. Classifying progestagens according to chemical groups, the relative risk increased significantly with increasing cumulative dose of levonorgestrel progestagen. It was difficult to conclude for the other groups due to lack of power. In a multivariate analysis the cumulative dose for all progestagen groups were non-significant, although we observed a significant increased risk with increasing milligram-months of estrogen exposure (p = 0.002). In conclusion, the increased risk of breast cancer related with OC formulations could be due mostly to estrogen component.

Validation of two global and generic quality of life questionnaires for population screening: SCREENQOL and SEQOL.

Population screening may harm quality of life (QoL), and traditional health-related QoL tools could be inadequate to evaluate this risk. Two global and generic QoL instruments were developed for studying the QoL consequences of screening (SCREENQOL), and QoL variation in a normal population (SEQOL). SCREENQOL and SEQOL (Self-Evaluation of Quality of Life Questionnaire) are self-administered questionnaires with items rated on 5-point Likert scales. SCREENQOL consists of 21 items measuring QoL across 6 different dimensions based upon validated QoL questionnaires. SEQOL consists of 317 items measuring QoL across 8 different dimensions, based on an integrative theory of QoL, a theoretical framework from a Danish QoL survey involving 7,222 persons 31 to 33 years old. For further validation, SEQOL and SCREENQOL were sent to 2,460 persons 18 to 88 years old randomly selected from the Danish Central Person Register together with Nottingham Health Profile (NHP) and Sickness Impact Profile (SIP). For SCREENQOL and SEQOL, test-retest reliability correlation was both >0.8, Cronbach's alpha was 0.65 and 0.75, correlation (r) to NHP was 0.67 and 0.49, to SIP 0.46 and 0.27, respectively (p

Birth weight as a predictor of breast cancer: a case-control study in Norway.

The hypothesis that birth weight is positively associated with adult risk of breast cancer implies that factors related to intrauterine growth may be important for the development of this malignancy. Using stored birth records from the two main hospitals in Trondheim and Bergen, Norway, we collected information on birth weight, birth length and placenta weight among 373 women who developed breast cancer. From the same archives, we selected as controls 1150 women of identical age as the cases without a history of breast cancer. Information on age at first birth and parity were collected from the Central Person Registry in Norway. Based on conditional logistic regression analysis, breast cancer risk was positively associated with birth weight and with birth length (P for trend=0.02). Birth weights in the highest quartile (3730 g or more) were associated with 40% higher risk (odds ratio, 1.4, 95% confidence interval, 1.1–1.9) of breast cancer compared to birth weights in the lowest quartile (less than 3090 g). For birth length, the odds ratio for women who were 51.5 cm or more (highest quartile) was 1.3 (95% confidence interval, 1.0–1.8) compared to being less than 50 cm (lowest quartile) at birth. Adjustment for age at first birth and parity did not change these estimates. Placenta weight was not associated with breast cancer risk. This study provides strong evidence that intrauterine factors may influence future risk of breast cancer. A common feature of such factors would be their ability to stimulate foetal growth and, simultaneously, to influence intrauterine development of the mammary gland.British Journal of Cancer (2002) 86, 89–91. DOI: 10.1038/sj/bjc/6600011 www.bjcancer.com© 2002 The Cancer Research Campaign

The schizophrenic patient in the somatic hospital.

There is an increased risk in schizophrenia for premature death from illnesses in almost all organic systems. The present study analyses the Rate Ratio (RR) for schizophrenic patients' admissions to somatic departments in Denmark. 20000 schizophrenic patients were identified in the Danish Psychiatric Central Register and 200000 sex- and age-matched controls were identified in the Danish Central Person Register. Both groups were searched for in the Danish National Patient Register in which admissions to all somatic departments are registered. Pulmonary and cardiovascular diseases are used as examples. RR is increased for several diseases, especially infectious, up to a maximum of RR = 4.15 for severe heart failures and decreased to as low as RR = 0.35 for atherosclerotic diseases of the brain vessels. It seems that individuals with schizophrenia are rarely treated for their physical illness in its early, less severe phases, but more likely in its acute phases when the disease is severe, life-threatening or painful.

The influence of previous low back trouble, general health, and working conditions on future sick-listing because of low back trouble. A 15-year follow-up study of risk indicators for self-reported sick-listing caused by low back trouble.

A 15-year follow-up study. To find risk indicators for self-reported sick-listing because of low back trouble and to evaluate which variables were the most important indicators of work incapacity resulting from low back trouble during the follow-up period of 15 years. The initial data were obtained from a health survey conducted in a general population from the Municipality of Glostrup, Denmark. The follow-up data included information from the Central Person Register, the Early Retirement Pension Register, and a postal questionnaire regarding self-reported sick-listing because of low back trouble. An epidemiologic study, in which logistic regression analyses were used for evaluation of the data. The model used consisted of the variable in question, age, gender, and previous experience of low back trouble, along with interactions. It was found that 22 of 37 variables were risk indicators for later self-reported sick-listing because of low back trouble during the preceding year or the 7 years before the date of follow-up evaluation. In analyzing the most significant variables simultaneously, it was found that information from the initial investigation about sick-listing in general during the previous 10 years, sciatic pain, use of analgesics for low back trouble, previous sick-listing because of low back trouble, and occupation were the most important risk indicators for self-reported work incapacity resulting from low back trouble during the follow-up period of 15 years. Findings showed that the strongest prognostic indicators of later sick-listing because of low back trouble involve information from the person about previous sick-listing behavior in general and previous experience of low back trouble episodes, especially if these had been accompanied by sciatic pain, use of analgesics, or previous low back trouble sick-listing.

Breast cancer risk among relatively young women employed in solvent‐using industries

Background Breast cancer is the most common tumor among women, and the causes remain almost unknown apart from changes in the reproductive pattern. Based on experimental evidence, some organic solvents may have carcinogenic properties to the female breast. Methods We used a comprehensive national data linkage to examine the adjusted breast cancer risk among relatively young (20–55 years) Danish women employed in industries with extensive use of organic solvents (i.e., the metal product, wood and furniture, printing, chemical, and textile and clothing industries). Relative risks (OR) were estimated from a matched case-control study on 7,802 women with breast cancer (1970–1989). Potential exposure to organic solvents was accessed from the duration of employment within the selected industries and reconstructed from the files of a nationwide compulsory pension fund. Socioeconomic status and the individual reproductive pattern were obtained from the central person registry. Results The adjusted OR for breast cancer after 15 years latency was increased in each of the selected industrial groups (from 1.4 to 2.4). For the entire group with over 10 years of employment, the OR was significantly elevated (twofold). Conclusions This study supports the observation that long-term occupational exposure to organic solvents may play a role in breast cancer risk. However, some residual confounding may exist, and further studies are required to identify specific carcinogenic organic solvents. Am. J. Ind. Med. 36:43–47, 1999. © 1999 Wiley-Liss, Inc.

Breast cancer risk among relatively young women employed in solvent-using industries.

Breast cancer is the most common tumor among women, and the causes remain almost unknown apart from changes in the reproductive pattern. Based on experimental evidence, some organic solvents may have carcinogenic properties to the female breast. We used a comprehensive national data linkage to examine the adjusted breast cancer risk among relatively young (20-55 years) Danish women employed in industries with extensive use of organic solvents (i.e., the metal product, wood and furniture, printing, chemical, and textile and clothing industries). Relative risks (OR) were estimated from a matched case-control study on 7,802 women with breast cancer (1970-1989). Potential exposure to organic solvents was accessed from the duration of employment within the selected industries and reconstructed from the files of a nationwide compulsory pension fund. Socioeconomic status and the individual reproductive pattern were obtained from the central person registry. The adjusted OR for breast cancer after 15 years latency was increased in each of the selected industrial groups (from 1.4 to 2.4). For the entire group with over 10 years of employment, the OR was significantly elevated (twofold). This study supports the observation that long-term occupational exposure to organic solvents may play a role in breast cancer risk. However, some residual confounding may exist, and further studies are required to identify specific carcinogenic organic solvents.

Mortality and causes of death of 344 Danish patients with systemic sclerosis (scleroderma)

To determine survival, mortality and causes of death in Danish patients with systemic sclerosis (scleroderma), and to analyse how these parameters are influenced by demographic variables and the extent of skin involvement. A cohort of 344 patients with incident systemic sclerosis (SSc) after 1 January 1960 was retrospectively identified, representing 3716 patient-years of follow-up. The vital status at the end of the study ultimo 1996 was established by reviewing the clinical charts and by contacting the Danish Central Person Register. The causes of death were based on information obtained from the hospital charts and the autopsy reports (80%) and death certificates (20%). The extent of skin sclerosis was described by means of a two-subset model (limited and diffuse involvement) and a three-subset model (digital, extremity and truncal involvement) in all patients. Expected numbers of deaths were calculated by means of age- and sex-specific mortality rates of the general Danish population. Crude mortality rates were 6.5 and 3.9%/yr, respectively, in men and women. The standardized mortality ratio (SMR) was 2.9 (95% CI 2.5-3.4) and was not significantly influenced by sex or age at disease onset. Mortality rates were significantly increased in patients with diffuse skin sclerosis (SMR 4.5, 95% CI 3.5-5.7) and patients under the age of 35 yr (SMR 13, 95% CI 2.7-37). Of the 160 patients who died during the study, 41 deaths (26%) were SSc related, accounting for one-third of the excess mortality. We found a significantly increased mortality in patients with SSc, particularly in the subset of patients with diffuse skin sclerosis and in young patients. The excess mortality was due to an increase in both the SSc-related mortality and the unrelated mortality. However, all other subsets also had a significantly increased risk of death, mainly due to an increased risk of death due to causes unrelated to SSc, cancer among others. The fact that the unrelated mortality in SSc was found to be 2-fold increased suggests that the excess mortality that was classified as unrelated should more appropriately be termed indirectly SSc related.

Genetic epidemiology of migraine and cluster headache.

Migraine. The present genetic epidemiological survey of migraine was based on semi-structured interviews by a physician. The operational diagnostic criteria of the International Headache Society were used. Three thousand males and 1,000 females aged 40 were drawn from the Danish National Central Person Registry. They received a questionnaire by post regarding migraine and the response rate was 87%. People with self-reported migraine and a random sample reporting no migraine were invited to a headache interview and physical and neurological examination. Those not reacting to the invitation were interviewed by telephone. The participation of the interview was 87%. Kappa was 0.77 validating self-reported migraine against a clinical interview by a physician. Non-responders did not differ from responders regarding migraine. The lifetime prevalence of MO and MA was 9.3% and 6.3% in males and 20.1% and 9.6% in females. People with MA were included as probands in the family study. An equivalent number of probands with MO and probands who had never had migraine were random samples of the people with MO) and those who had never had migraine, respectively. First-degree relatives and spouses were interviewed blindly by a physician. The 378 probands had 1,109 first-degree relatives and 229 spouses. Compared with the general population, the first-degree relatives of probands with MO had a 1.9-fold increased risk of MO and a 1.4-fold increased risk of MA, after standardization for sex and age. The first-degree relatives of probands with MA had a 3.8-fold increased risk of MA and no increased risk of MO. The first-degree relatives of probands who had never had migraine had no increased risk of either MO or MA. Spouses to pro-bands with MC) had a 1.5-fold increased risk of MO, while spouses to probands with MA had no increased risk of MA. The familial patterns indicate that MO and MA are distinct entities. The familial occurrence suggests that MO is caused by a combination of genetic and environmental factors, while MA is determined mainly or exclusively by genetic factors. The complex segregation analysis supports the importance of genetic factors and suggests multifactorial inheritance without generational difference in both MO and MA, but genetic heterogeneity cannot be excluded.

A longitudinal study on subjective and objective orthodontic treatment need.

The purpose of the study was to analyse changes in professionally-defined need and self-perceived need between the ages of 12-20 years. In 1985, occlusion and perceived need for treatment were recorded in 306 12-year-olds (born 1973) living in five communes in Finnmark, the most northern part of Norway. In 1993-94, 271 of the individuals were traced through the Norwegian Central Person Register and invited in letters to attend a clinical examination and an interview. A total of 80 individuals responded, with a mean age of 20.7 years. Professionally-defined need was assessed according to the Need for Orthodontic Treatment Index (NOTI) which is used by the Norwegian Health Insurance System for reimbursement of treatment costs. Change in category of need between 12-20 years was used as a measurement of health gain. Perceived need was measured by the individuals' responses to a question about desire for treatment. Individuals who received treatment (n = 22) showed an improvement in occlusion (health gain) corresponding on average to one category of need. The occlusal status of the untreated individuals was unchanged. All the individuals that desired treatment at 12 years of age (n = 15) did not want treatment at 20, and they were satisfied with their dental arrangement. Most of these individuals had received treatment, but a few with minor malocclusions had at age 12 been informed about the small objective need and refrained from treatment. All the individuals that wanted treatment at 20 years of age, 29 per cent of the total sample, had not desired treatment at 12 years of age. The results underline the importance of information and education during orthodontic counselling of potential patients.

Residual urine in 75-year-old men and women. A normative population study.

The prevalence of residual urine in elderly people in the community is poorly documented. The aim of the present study was to assess the prevalence and range of residual urine in elderly people in the community. As part of a major epidemiologic study (The Glostrup Population Study), 140 75-year-old men and women were included in this study (92 men, 48 women). All were selected at random from the Central Person Register by age and residence. All had a single sonographic measurement of residual urine with a prevoid volume of 150 ml or more. More than 10 ml of residual urine was found in 91 of the 92 men (median 90 ml; range 10-1502 ml), and in 44 of the 48 women (median 45 ml; range 0-180 ml). Our figures correspond to those previously reported in selected patient populations. It must be emphasized, however, that our findings are merely descriptive, as the clinical significance of a single residual urine determination is questionable.