Record-based Case-control Study Research Articles

IJCM_339A: Risk Factors for Spontaneous Intracerebral Haemorrhage in Tertiary Care Hospitals of Mangalore: A Case Control Study

Background: Intracerebral haemorrhage (ICH) is the rupture of an intra- parenchymal vessel resulting in haemorrhage within the brain, often associated with stroke. The study was done to determine the association of intracerebral haemorrhage with duration of hypertension and other lifestyle factors among the adult patients. The study also includes association of the volume of ICH and its determinants related to hypertension. Methodology: A Record based Case Control study with cases involving the patient with ICH admitted to study hospital between January 1st 2014 and 31st December 2015 and control involving age and sex matched patients admitted during the study period. Results: Of the 118 patients, 41 cases (69.5%) and 12 controls (20.3%) had hypertension, with odds ratio 8.93. 40% of cases were suffering from hypertension for 5 years. 18.6% of ICH patients gave history of tobacco consumption and 30.5% gave history of alcohol consumption. 57.2% and 60% of ICH patients consumed tobacco and alcohol for more than 10 years respectively. Mean volume of intracerebral bleed in patients with hypertension is 12.4ml and without hypertension is 3.45ml. 23 patients had systolic BP more than 140mm of Hg and an average bleed of 10.33ml. Conclusion: ICH is the second commonest type of stroke, ischemic being the first one. Hypertension is the risk factor for ICH. Volume of bleed was higher among the patient who were hypertensive for longer duration and who had increased systolic BP.

IJCM_318A: Risk Factors for Anaemia among Type 2 Diabetes Mellitus Patients in Mangalore- A Case Control Study.

Background: Anaemia, a common haematological abnormality, currently stands at a prevalence rate of 24.8% worldwide and 39.86% in India, affecting 1.62 billion individuals overall. Studies have shown that patients with Diabetes are twice as likely to be prone to anaemia. Objective: To study the risk factors for anaemia among patients with type 2 Diabetes Mellitus. Methodology: This is a record-based case-control study of 50 cases (diabetic with anaemia) and 100 controls (diabetic without anaemia) in Government Wenlock Hospital, Mangalore. Patients with haemoglobin concentration below the normal level (as defined by WHO as <13 g/dl for men and <12 g/dl for women) were considered anaemic. Data was entered and analyzed using the statistical software SPSS Version 17.0. Univariate analyses and a Chi-Square test were conducted to identify risk factors. Results: The median age of cases as well as controls was 60 years. The duration of diabetes was 8 years in cases and 7 years in controls. Among 50 cases, there were 39 (78%) males and 11(22%) females and among 100 controls, 68(68%) males and 32(32%) females. On univariate analysis, it was found that the low serum urea, creatinine, albumin, total protein and calcium levels were significantly associated with the presence of anaemia (P <0.05). Conclusion: The above parameters implicate impairment in renal function and hence we can conclude that impaired renal function is a risk factor for developing anaemia in type 2 Diabetes Mellitus patients.

Immediate cause and the role of multimorbidity in deaths associated with COVID 19 among hospitalized patients in a low resource district in Kerala India: A record-based case-control analysis.

Multimorbidity is the coexistence of two or more chronic medical conditions in a person. The study aims to investigate the immediate cause of death and risk factors of mortality including multimorbidity among patients hospitalized with SARS CoV2 infection in Kasaragod district in Kerala, India. A record-based case-control study was done using the hospital records and follow-up surveillance system of SARS-COV 2 patients admitted in the Kasaragod district. SARS-COV 2 patients who had expired during the study period from June to December 2020 and reported as COVID-19 deaths (N = 226) were the cases, and an equal number of hospital controls were the study participants. The mean (SD) age of the cases and controls were found to be 64.6 (14.2) years and 61.5 (13.4) years, respectively. Covid pneumonia alone was reported as the cause of death in more than half (52%) of the study participants. This was followed by cardiovascular events (8.5%) and acute kidney injury (6.5%). Among individual comorbidities among people who expired, diabetes mellitus (53%) was the most common, followed by hypertension (46%) and cardiovascular diseases (23%). More than 50% were found to have multimorbidity. Logistic regression showed chronic kidney disease (CKD) (Adjusted odds ratio (AOR) = 2.18 (1.24-3.83)) and malignancy (AOR = 3.05 (1.27-7.32)) to be significantly associated with mortality as individual determinants. Hypertension-diabetes mellitus [AOR = 1.68 (1.02-2.76), P = 0.043] and hypertension-CKD [AOR = 3.49 (1.01-12.01), P = 0.48] dyads were multimorbidities significantly associated with mortality. Combinations of hypertension with diabetes mellitus and CKD were found to be significant determinants for mortality in hospitalized COVID-19 patients. Uniformity in death certification is required to understand the causes and contributors to death in COVID-19.

Vertebrobasilar Artery Calcification as a Risk Factor for the Development of Stroke: Case-Control Study From a Tertiary Care Center, Southern India.

Background Stroke is an important cause of morbidity and mortality in developing countries. Many risk factors are well-established for the development of stroke. Atherosclerosis involving the media and intima layer of vertebrobasilar arteries has not been studied well as a risk factor for stroke. Objective To assess the degree of calcification of vertebrobasilar arteries among patients with stroke (cases), age- and gender-matched controls, and the risk of the development of stroke. Methods This was a hospital record-based case-control study with individuals with stroke as cases and age- and gender-matched individuals without stroke as controls, who underwent computed tomography imaging. The degree of calcification of vertebrobasilar arteries was assessed among cases and controls. Various other risk factors for the development of stroke such as the presence of hypertension, diabetes mellitus, and impaired lipid profile were also assessed. Results Among the 150 cases and their age- and gender-matched controls, the mean age of the subjects was 58.38 (±14.06) years. Forty percent of the individuals were males. Among the cases, right vertebral, left vertebral, and basilar artery calcifications were observed among 114 (76%), 102 (68%), and 52 (34.7%), respectively. Among controls, 71 (47.3%), 77 (51.3%), and 29 (19.3%) individuals had right vertebral, left vertebral, and basilar artery calcifications, respectively. The degree of calcification was higher among the cases in the right and left vertebral arteries than the controls (adjusted odds (aOR) of 6.61 and 2.32 and p-value <0.001 and 0.032, respectively). The risk of stroke increased with higher degrees of calcification, the presence of diabetes mellitus, and raised cholesterol levels (aOR of 9.98, 2.32, and 4 and p-value <0.001, 0.007, and 0.001, respectively). The risk of stroke increases with the presence of multiple risk factors. Conclusion The presence of higher grades of calcifications in the vertebrobasilar arteries is a major risk factor for stroke. Hence, its presence in asymptomatic individuals needs to be taken as a warning sign for the development of stroke.

Commercial outdoor plant nurseries as a confounder for electromagnetic fields and childhood leukemia risk.

BackgroundClose residential proximity to powerlines and high magnetic fields exposure may be associated with elevated childhood leukemia risks as reported by prior studies and pooled analyses. Magnetic fields exposure from high-voltage powerlines is associated with proximity to these powerlines and consequently with any factor varying with distance. Areas underneath powerlines in California may be sites for commercial plant nurseries that can use pesticides, a potential childhood leukemia risk factor. ObjectivesAssess if potential pesticide exposure from commercial plant nurseries is a confounder or interacts with proximity or magnetic fields exposure from high-voltage powerlines to increase childhood leukemia risk. MethodsA comprehensive childhood leukemia record-based case-control study with 5788 cases and 5788 controls (born and diagnosed in California, 1986–2008) was conducted. Pesticide, powerline, and magnetic field exposure assessment utilized models that incorporated geographical information systems, aerial satellite images, site visits and other historical information. ResultsThe relationship for calculated fields with childhood leukemia (odds ratio (OR) 1.51, 95% confidence interval (CI) 0.70–3.23) slightly attenuated when controlling for nursery proximity (OR 1.43, 95% CI 0.65–3.16) or restricting analysis to subjects living far (>300 m) from nurseries (OR 1.43, 95% CI 0.79–2.60). A similar association pattern was observed between distance to high-voltage powerlines and childhood leukemia. The association between nursery proximity and childhood leukemia was unchanged or only slightly attenuated when controlling for calculated fields or powerline distance; ORs remained above 2 when excluding subjects with high calculated fields or close powerline proximity (OR 2.16, 95% CI 0.82–5.67 and OR 2.15, 95% CI 0.82–5.64, respectively). The observed relationships were robust to different time periods, reference categories, and cut points. DiscussionClose residential proximity to nurseries is suggested as an independent childhood leukemia risk factor. Our results do not support plant nurseries as an explanation for observed childhood leukemia risks for powerline proximity and magnetic fields exposure, although small numbers of subjects concurrently exposed to high magnetic fields, close powerline proximity and plant nurseries limited our ability to fully assess potential confounding.

Residential proximity to plant nurseries and risk of childhood leukemia

BackgroundPesticides are a potential risk factor for childhood leukemia. Studies evaluating the role of prenatal and/or early life exposure to pesticides in the development of childhood leukemia have produced a range of results. In addition to indoor use of pesticides, higher risks have been reported for children born near agricultural crops. No studies have looked at pesticide exposure based on proximity of birth residence to commercial plant nurseries, even though nurseries are located much closer to residences than agricultural crops and can potentially result in chronic year-round pesticide exposure. ObjectivesTo evaluate whether risk of childhood leukemia is associated with pesticide use as determined by distance of residence at birth to commercial, outdoor plant nurseries. MethodsWe conducted a large statewide, record-based case-control study of childhood leukemia in California, which included 5788 childhood leukemia cases and an equal number of controls. Pesticide exposure was based on a spatial proximity model, which combined geographic information system data with aerial satellite imagery. ResultsOverall, the results supported an increased childhood leukemia risk only for birth residences very close to nurseries. For birth residences less than 75 m from plant nurseries, we found an increased risk of childhood leukemia (odds ratio (OR) 2.40, 95% confidence interval (CI) 0.99-5.82) that was stronger for acute lymphocytic leukemia (OR 3.09, 95% CI 1.14-8.34). DiscussionThe association was robust to choices of reference group, cut points and data quality. Our findings suggest that close proximity to plant nurseries may be a risk factor for childhood leukemia and that this relationship should be further evaluated.

Increased Risk of Parkinson's Disease in Patients With Schizophrenia Spectrum Disorders.

PD comorbid with schizophrenia has been considered rare because these diseases associate with opposite alterations in the brain dopamine system. The objective of this study was to investigate the risk of PD after a diagnosis of a schizophrenia spectrum disorder. Regionally, this was a retrospective record-based case-control study. The cohort included 3045 PD patients treated 2004-2019 in southwestern Finland. Nationally this was a nested case-control study using registers to examine Finnish patients who received a clinically confirmed PD diagnosis 1996-2015 (n=22,189). PD patients with previously diagnosed schizophrenia spectrum disorder (separate analysis for schizophrenia) were included. Comparable non-PD control groups were derived from both data sets. All PD diagnoses were based on individual clinical examinations by certified neurologists. In PD patients, the prevalence of earlier schizophrenia spectrum disorder was 0.76% in regional data and 1.50% in nationwide data. In age-matched controls, the prevalence in the regional and national data was 0.16% and 1.31%, respectively. The odds ratio for PD after schizophrenia spectrum disorder diagnosis was 4.63 (95% CI, 1.76-12.19; P < 0.01) in the regional data and 1.17 (95% CI, 1.04-1.31; P < 0.01) in the national data. Schizophrenia spectrum disorder increases the risk of PD later in life. This association was observed in both individual patient data and nationwide register data. Therefore, despite the opposite dopaminergic disease mechanisms, schizophrenia spectrum disorder increases rather than decreases the risk of PD. The increased PD risk could be related to risk-altering effects of dopamine receptor antagonists or to the increased vulnerability of the dopamine system induced by illness phase-dependent dopamine dysregulation in schizophrenia/schizophrenia spectrum disorder. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Risk Factors Associated with Fatal Dengue Hemorrhagic Fever in Adults: A Case Control Study.

Background Dengue is endemic in most parts of the tropics with a significant mortality of 1–5%. Although individual case reports and case series have been published, large-scale case controls studies are few. The objective of this study was to find clinical and laboratory predictors of mortality in dengue. Methods Hospital case record based case control study was performed. Results Twenty fatalities with 80 controls were analyzed. Clinical parameters of postural dizziness (OR 3.2; 95% CI 1.1–8.9), bleeding (OR 31.9; 95% CI 6.08–167.34), presence of plasma leakage (OR 64.6; 95% CI 7.45–560.5), abdominal tenderness (OR 2.24; 95% CI 0.79–6.38), and signs of cardiorespiratory instability at admission increased the risk of dying from dengue. Altered consciousness was exclusively seen in 20% of cases. Laboratory parameters of elevated CRP (OR 1.652; 95% CI 1.28–2.14), AST, or ALT > 500 IU/L (OR 52.5; 95% CI 12.52–220.1) and acute kidney injury (AKI) (OR 103.5; 95% CI 13.26–807.78) during hospital stay increased the odds of dying. Need for assisted ventilation and multiorgan dysfunction (MOD) were exclusively seen in the cases. Multivariate logistic regression revealed bleeding at admission, AKI, and elevated hepatic transaminase >500 IU/L to be independent predictors of mortality. Conclusions This case control study revealed that mortality from dengue could be predicted using clinical parameters at admission and low cost routine laboratory investigations.

Maternal factors associated with low birth weight: a case control study in rural Kerala

Background: Low birth weight (LBW) continues to remain a major public health problem worldwide. There are numerous factors contributing to LBW both maternal and foetal. The maternal risk factors are biologically and socially interrelated. The mortality of low birth weight can be reduced if the maternal risk factors are detected early and managed by simple techniques. This study was conducted to study the maternal risk factors associated with low birth weight. Methods: A retrospective record based case control study was conducted. Retrospective data collection was done using registers from medical record section of Obstetrics and Gynaecology department. After applying exclusion criteria and checking for completeness of records, we selected 60 cases and 124 matched controls. Data was entered in Microsoft excel and analyzed using SPSS version 16. Students ‘t’ test, chi-square test and odds ratio were used to find out the factors associated with low birth weight. Results: In the present study, 60 cases and 124 controls were studied. Mean age of mothers in the case group was 24.4±4.7 yrs. and in the control group was 24.8±4.42 yrs. Mean weight of the cases was 62.5±6.89 kg and of the controls was 65.04±7.16 kg. A total of 35% of the cases and 20% of the controls suffered from pregnancy related diseases. Conclusions: Maternal factors like Socio-economic status, weight, haemoglobin and parity were significantly associated with LBW. Maternal diseases like hypertension, diabetes can result in LBW baby.

Residential magnetic fields exposure and childhood leukemia: a population-based case-control study in California.

Studies have reported an increased risk of childhood leukemia associated with exposure to magnetic fields. We conducted a large records-based case-control study of childhood leukemia risk and exposure to magnetic fields from power lines in California. The study included 5,788 childhood leukemia cases (born in and diagnosed in California 1986-2008) matched to population-based controls on age and sex. We calculated magnetic fields at birth addresses using geographic information systems, aerial imagery, historical information on load and phasing, and site visits. Based on unconditional logistic regression controlling for age, sex, race/ethnicity, and socioeconomic status using subjects geocoded to a basic standard of accuracy, we report a slight risk deficit in two intermediate exposure groups and a small excess risk in the highest exposure group (odds ratio of 1.50 (95% confidence interval [0.70, 3.23])). Subgroup and sensitivity analyses as well as matched analyses gave similar results. All estimates had wide confidence intervals. Our large, statewide, record-based case-control study of childhood leukemia in California does not in itself provide clear evidence of risk associated with greater exposure to magnetic fields from power lines, but could be viewed as consistent with previous findings of increased risk.

Risk factors of mortality among dengue patients admitted to a tertiary care setting in Kerala, India

Dengue is one of the most serious and rapidly emerging tropical mosquito-borne diseases. The state of Kerala in India is hyperendemic for the disease and is one of the leading states in the reporting of deaths due to dengue. As primary prevention of dengue has had limited success, the prevention of mortality through the identification of risk factors and efficient patient management is of utmost importance. Hence, a record-based case control study was conducted in the Medical College Hospital in Thiruvananthapuram to identify the risk factors of mortality in patients admitted with dengue. Dengue patients over 40years of age were 9.3 times (95% CI; 1.9-44.4) more likely to die compared with younger patients. The clinical features associated with mortality from dengue were altered sensorium (odds ratio (OR) - 156, 95% CI; 12.575-1935.197), abnormal reflexes (OR - 8.5, 95% CI; 1.833-39.421) and edema (OR - 13.22, 95% CI; 2.651-65.951). Mortality was also higher in those patients with co-morbidities such as diabetes mellitus (OR - 26, 95% CI; 2.47-273.674) and hypertension (OR - 44, 95% CI; 6.23-315.499). The independent predictors of mortality were altered sensorium and hypertension. Dengue fever patients with these clinical features and those who are elderly should be more rigorously monitored and promptly referred from lower settings when required to reduce mortality.

Results of a record-based case-control study of natural background radiation and the incidence of childhood cancers in Great Britain

Background Although there is abundant evidence that moderate and high doses of radiation can cause leukaemia and other cancers, there is little direct evidence on the leukaemogenic (or other carcin...

A record-based case–control study of natural background radiation and the incidence of childhood leukaemia and other cancers in Great Britain during 1980–2006

We conducted a large record-based case-control study testing associations between childhood cancer and natural background radiation. Cases (27,447) born and diagnosed in Great Britain during 1980-2006 and matched cancer-free controls (36,793) were from the National Registry of Childhood Tumours. Radiation exposures were estimated for mother's residence at the child's birth from national databases, using the County District mean for gamma rays, and a predictive map based on domestic measurements grouped by geological boundaries for radon. There was 12% excess relative risk (ERR) (95% CI 3, 22; two-sided P=0.01) of childhood leukaemia per millisievert of cumulative red bone marrow dose from gamma radiation; the analogous association for radon was not significant, ERR 3% (95% CI -4, 11; P=0.35). Associations for other childhood cancers were not significant for either exposure. Excess risk was insensitive to adjustment for measures of socio-economic status. The statistically significant leukaemia risk reported in this reasonably powered study (power ~50%) is consistent with high-dose rate predictions. Substantial bias is unlikely, and we cannot identify mechanisms by which confounding might plausibly account for the association, which we regard as likely to be causal. The study supports the extrapolation of high-dose rate risk models to protracted exposures at natural background exposure levels.

Haemophilusinfluenzae type b conjugate vaccine for preventing pneumonia in infants hospitalized for bronchiolitis: A case–control study

Haemophilus influenzae type b (Hib) conjugate vaccine reduces the risk of pneumonia in infants. To determine the effect of Hib conjugate vaccine (HibCV) on the prevention of pneumonia as a complication among infants hospitalized for bronchiolitis. This record-based case-control study was conducted at The Children's Hospital "Dr. Ovidio Aliaga U" in La Paz, Bolivia during 2003 and 2004. Cases were infants hospitalized for bronchiolitis under 1 year of age who developed radiological pneumonia during hospitalization. Controls were patients who had good clinical progress without the use of antibiotics. Pneumonia was defined by alveolar consolidation on chest X-ray that justified the use of antibiotics. Eighty patients were studied (16 cases and 64 controls). Their median age was 4.5 months. Demographic and clinical features were similar in both groups, except for a higher proportion of vomiting (56.3% vs. 28.1%; p<0.05) in the case group. The percentage of unvaccinated infants was significantly higher in cases (68.8% vs. 26.6%; p<0.05) and the length of hospital stay longer (8.5+/-5.4 vs. 3.1+/-2.2 days; p<0.05). There was a strong association between unvaccinated infants and the occurrence of pneumonia as a complication (odds ratio 6.1, 95% confidence interval 1.8-20.1; p<0.01). Unvaccinated infants admitted for bronchiolitis have a higher risk of radiologically confirmed pneumonia. Larger studies are needed to validate these results and reconsider the burden of Hib infection among infants in less developed countries.

Hospital-Based Case-Control Study of Bronchiectasis in Indigenous Children in Central Australia

Childhood pneumonia has been reported to be associated with the development of bronchiectasis but there are no case-control studies that have examined this. This study examined the relationship between hospital admission for episode(s) of pneumonia and the risk of radiologically proven bronchiectasis. A medical record-based case-control study of bronchiectasis in Indigenous children was conducted in Central Australia. Controls (183), matched to cases (61) by gender, age and year of diagnosis, were Indigenous children hospitalized with other conditions. There was a strong association between a history of hospitalized pneumonia and bronchiectasis [odds ratio (OR), 15.2; 95% confidence interval (95% CI) 4.4-52.7]. This was particularly evident in recurrent hospitalized pneumonia (P for trend < 0.01), severe pneumonia episodes with longer hospital stay (P for trend < 0.01), presence of atelectasis (OR 11.9; 95% CI 3.1-45.9) and requirement for oxygen (P for trend < 0.01). The overall number of pneumonia episodes, rather than its site, was associated with bronchiectasis. Although the total number of pneumonia episodes in the first year of life did not increase the risk of bronchiectasis, more severe episodes early in life did. Malnutrition, premature birth and being small for gestational age were more common findings among cases. Breast-feeding appeared to be a protective factor (OR 0.2; 95% CI 0.1-0.7). Although we cannot fully answer the question of why bronchiectasis is much more common in Indigenous children, we have provided strong evidence of an association between bronchiectasis and severe and recurrent pneumonia episodes in infancy and childhood.

The Relation of Gastroesophageal Reflux Disease and Its Treatment to Adenocarcinomas of the Esophagus and Gastric Cardia

To examine the relationship of gastrointestinal disorders and their treatment to the risk of adenocarcinomas of the esophagus and gastric cardia (AEC). A medical record-based case-control study, with data collected on a standardized form by a trained abstractor, blind to the case-control status. A large prepaid health plan. Case patients were plan members newly diagnosed with histologically confirmed AEC from 1986 to 1992. For each of the 196 eligible case patients, one control was selected who matched for membership at time of diagnosis, sex, year of birth, and duration of membership. Association between AEC and history of gastroesophageal conditions and their treatment. Conditional logistic regression procedures were used for calculation of odds ratios (ORs) and corresponding 95% confidence intervals (Cls), with adjustment for race, smoking status, and body mass index. Medications were grouped into H2 antagonists (cimetidine, ranitidine, famotidine, and nizatidine) and anticholinergics (propantheline bromide, dicyclomine hydrochloride, Donnatal [combination of atropine sulfate, hyoscyamine sulfate, phenobarbital, and scopolamine hydrobromide], and Librax [combination of chlordiazepoxide hydrochloride and clidinium bromide]). Significant twofold or greater risks of AEC were associated with a history of esophageal reflux, hiatal hernia, esophagitis/esophageal ulcer, and difficulty swallowing. The ORs increased with increasing number of these conditions. Although a fourfold risk was linked to four or more prescriptions for H2 antagonists, the risk was reduced to 1.5 (95% Cl, 0.4 to 5.4) after adjusting for the predisposing conditions. Further analysis revealed that the excess risk was restricted to persons with a history of gastroesophageal reflux and related conditions. No association was observed for overall use of anticholinergics. However, after adjustment for predisposing conditions, ORs decreased with increasing number of prescriptions for anticholinergics (P for trend = .08) This study provides reassuring findings that use of H2 antagonists and anticholinergics does not increase AEC risk. It also quantifies the elevated risk of AEC associated with gastroesophageal reflux disease. Further research into reflux disease and the production of premalignant epithelial changes may help elucidate carcinogenic mechanisms and measures aimed at early detection and prevention of AEC.

Bromocriptine and Puerperal Seizures

Case reports have prompted concern that the use of bromocriptine mesylate to prevent lactation in the puerperium increases the risk of postpartum seizure. We conducted a record-based case-control study of postpartum seizures in three data bases to evaluate this relation. We identified 43 women who had a postpartum seizure, and we matched 319 controls individually by hospital of delivery, quinquenium of age, and time of delivery. Overall, women taking bromocriptine had a 22% lower risk for seizures, that is, the relative risk estimate was 0.78, with a 90% confidence interval of 0.29 to 1.87. A reduction in seizure risk is consistent with reports of antiseizure activity for bromocriptine in various species, including humans. We found a small positive association between bromocriptine use and seizures occurring more than 72 hours after delivery, with a relative risk estimate of 1.6 after controlling for seizure history. This association was offset by a strong negative association between bromocriptine use and early-occurring seizures. The pattern of an initial reduced risk followed by an increase to normal or above-normal levels of risk could result from an antiseizure activity of bromocriptine, with a rebound in risk when bromocriptine is withdrawn.

Serum cholesterol and primary brain tumours: a case-control study.

The objective of this study was to test the hypothesis that a positive relationship exists between high levels of serum cholesterol and primary brain tumours. A record-based case-control study was performed on male Jewish residents of Israel who were hospitalized at the Hadassah Ein Karem hospital in the years 1978-1982. A record check identified 37 cases of brain tumour who fulfilled the criteria for inclusion in the study and whose hospital files included the necessary data. For each case two controls were chosen randomly from all patients with inguinal hernia who met the respective matching criteria of age and year of hospitalization. The mean cholesterol value of the cases with brain tumours was 22 mg dl-1 higher than that of the controls. This difference was statistically significant (P = 0.007). Controlling for weight, region of birth, season of year, social class, medications and length of hospitalization before the measurement of cholesterol did not reduce the cholesterol difference, and in some instances increased it.