Statewide Hospital Discharge Database Research Articles

Children hospitalized early and increased risk for future serious injury

Objective—To determine if infants hospitalized for any reason before 90 days of age are at increased risk for future serious injury. Setting—Washington State. Methods—A population based retrospective cohort study, using...

Invasive pneumococcal disease in the population of Victoria.

To estimate morbidity and mortality rates for invasive Streptococcus pneumoniae (pneumococcal) disease in the non-Indigenous population of Victoria. Survey using data from a statewide voluntary laboratory surveillance scheme (1989-1998), statewide hospital discharge database (1995-1998), medical records of notified patients (1994-1995) and serotyping of notified isolates (1994-1998). Incidence of pneumococcal bacteraemia and pneumonia; predisposing factors; serotypes of isolates. Minimum estimates of annual incidence of invasive disease, based on laboratory surveillance data for 1995-1998, were 59 per 100,000 for children aged < 2 years, 25 per 100,000 for people aged > or = 65 years, and 8 per 100,000 overall. Annual incidence of pneumococcal pneumonia, calculated from hospital discharge data, was 99 per 100,000 for those aged > or = 65 years. Manifestations of invasive pneumococcal disease varied with age, with meningitis more common in infants, and pneumonia most common in older patients. A predisposing factor for pneumococcal infection was present in 48% of patients. Most isolates from infants (83%) belonged to serotypes in the proposed seven-valent infant vaccine, and 91% of isolates from people aged > or = 2 years belonged to serotypes in the current 23-valent adult vaccine. S. pneumoniae continues to be a major cause of morbidity and mortality in young children and the elderly in Victoria. More widespread use of the currently available pneumococcal vaccine in adults and introduction of an effective vaccine for infants should greatly reduce incidence of the disease.

Myocardial infarction and acute cholecystitis: an application of sequence symmetry analysis.

Using a statewide hospital discharge database and a novel epidemiology method, sequence symmetry analysis (Epidemiology. 1996;7:478-84), I examined the relative risk for hospital admission for acute cholecystitis after admission for myocardial infarction. In sequence symmetry analysis, the ratio of the number of subjects in a fixed population who experienced two events in a "causal" vs "noncausal" temporal sequence estimates the incidence rate ratio (IRR). Of 514 patients admitted for both myocardial infarction and acute cholecystitis during a 3-year window period, 295 were admitted for myocardial infarction first and 219 for acute cholecystitis first, yielding a null sequence-adjusted IRR of 1.45 [95% confidence interval (CI) = 1.28-1.64]. A similar analysis for a known relation (myocardial infarction-->congestive heart failure, N = 27,850) showed the expected association [adjusted IRR = 1.92 (95% CI = 1.88-1.95)], whereas an analysis for a relation hypothesized not to be strong (congestive heart failure-->acute cholecystitis, N = 775) showed only a small association [adjusted IRR = 1.16 (95% CI = 1.05-1.28)]. Subgroup analysis revealed time courses that supported each relation as causal. Hospitalization for myocardial infarction may increase the risk for subsequent hospitalization for acute cholecystitis.

Hospitalization for motor vehicle injuries among American Indians and Alaska natives in Washington

Objective: Little is known about the epidemiology of hospitalization for motor vehicle injury among American Indians and Alaska Natives (AI/ANs) in the Pacific Northwest. Current secondary data sources are inadequate to track this significant health problem. The purpose of this study was to determine the rate of hospitalization for motor vehicle injury in this population through linkage of Indian Health Service (IHS) patient registration data to a statewide hospital discharge database. Methods: To create the numerator, IHS patient registration data were linked to Washington State hospital discharge abstracts from 1990 to 1994 for motor vehicle injury (ICD-9 E-codes 810-819). The denominator for this population was derived from the total number of IHS enrollees in 1992. Comparative numerator and denominator data for all residents were derived from the discharge database and Washington State intercensal population estimates, respectively. Results: AI/ANs experienced a nearly two-fold higher rate of motor vehicle injury hospitalization ( N = 588) compared to all residents [Incidence Ratio (I.R.): 1.82; 95% C.I. 1.52–2.19]. The greatest disparity in incidence rates occurred among 25–34 year olds (I.R. 2.18; 95% C.I. 1.53–3.10) and 35–44 year olds (I.R. 2.18; 95% C.I. 1.36–3.47). In-hospital mortality, severity of injury and length of stay were not different between the 2 groups. Median charges for American Indian hospitalizations were $6188 and the IHS was payer in, at most, 24% of hospitalizations. Conclusions: AI/ANs are at higher risk of hospitalization for motor vehicle injuries but, compared to all residents of Washington, appear to have similar severity of injuries and outcomes. Motor vehicle injury hospitalization among AI/ANs incurs substantial health care costs.

Penile prosthesis implantation surgery: a statewide population based analysis of 2354 patients.

Minimally invasive therapy for erectile dysfunction (ED) has changed the frequency of penile prosthesis surgery. The purpose of this study is to describe the changes in frequency, hospital stay, hospital charges and penile prosthesis type in North Carolina. The data source was a statewide hospital discharge database which includes data on hospitalized patients for all 151 hospitals in North Carolina. From 1988-1993, 2354 patients underwent implantation of penile prostheses. The total number of penile prostheses implanted has declined over this six year period. Similarly, hospital stay has declined from an average of 4.03-2.96 d with a 46.6% decrease in total hospital days. Despite this change in hospital stay, hospital charges rose significantly from an average of $7252.48 to $12,842.18 driving total charges from $2973,516.80 to $3,826,969.60 (1993) representing a 28.7% increase. Minimally invasive therapy and changes in reimbursement have had a major impact on the number of patients undergoing penile prosthesis implantation for ED. This downward trend may continue as more treatment options develop from the marked increase in research in this field. However, this may result in an increase of patients seeking treatment overall.

The importance of surgeon experience for clinical and economic outcomes from thyroidectomy.

To determine whether individual surgeon experience is associated with improved short-term clinical and economic outcomes for patients with benign and malignant thyroid disease who underwent thyroid procedures in Maryland between 1991 and 1996. There is a prevailing belief that surgeon experience affects patient outcomes in endocrine surgery, but there is a paucity of objective evidence outside of clinical series published by experienced surgeons that supports this view. A cross-sectional analysis of all patients who underwent thyroidectomy in Maryland between 1991 and 1996 was conducted using a computerized statewide hospital discharge data base. Surgeons were categorized by volume of thyroidectomies over the 6-year study period: A (1 to 9 cases), B (10 to 29 cases), C (30 to 100 cases), and D (>100 cases). Multivariate regression was used to assess the relation between surgeon caseload and in-hospital complications, length of stay, and total hospital charges, adjusting for case mix and hospital volume. The highest-volume surgeons (group D) performed the greatest proportion of total thyroidectomies among the 5860 discharges, and they were more likely to operate on patients with cancer. After adjusting for case mix and hospital volume, highest-volume surgeons had the shortest length of stay (1.4 days vs. 1.7 days for groups B and C and 1.9 days for group A) and the lowest complication rate (5.1 % vs. 6.1% for groups B and C and 8.6% for group A). Length of stay and complications were more determined by surgeon experience than hospital volume, which had no consistent association with outcomes. Individual surgeon experience is significantly associated with complication rates and length of stay for thyroidectomy.

Specialists Achieve Better Outcomes Than Generalists for Lung Cancer Surgery

A push toward care provided by generalists as opposed to specialists has occurred in the health-care marketplace despite a lack of provider specific outcome data. The objective of this study was to determine whether the outcome of patients undergoing lung cancer surgery is different between general surgeons (GSs) and thoracic surgeons (TSs). Examination of data from a state-wide severity-adjusted administrative hospital discharge database. Patients undergoing lung cancer resection in all nonfederal acute care hospitals within South Carolina. Mortality by specialty adjusted for case mix. From 1991 to 1995, 1,720 resections for lung cancer were performed in South Carolina. One hundred thirty-seven cases were excluded because surgeons did not meet the predefined criteria for board certification, leaving 1,583 resections for analysis. One-half of lobectomies and nearly 60% of pneumonectomies were performed by GSs. Patients were similar in age, sex, gender, race, and the proportion in each severity of illness subclass. Mortality was significantly higher in patients who underwent lobectomy by GSs vs TSs (5.3% vs 3.0%; p<0.05) and in patients with extreme comorbidities (43.6% vs 25.4%; p=0.03) or age >65 years (7.4% vs 3.5%; p<0.05). Seventy percent of TSs performed > 10 cases in the series, whereas 75% of GSs performed <10 (p=0.05). Logistic regression analysis failed to identify any significant variable that might explain the mortality differences between TSs and GSs. Mortality is lower for lung cancer resection when the surgery is performed by a TS.

5-year reoperation rates after different types of lumbar spine surgery.

Population-based cohort study of Washington State patients who underwent lumbar spine surgery for degenerative conditions in 1988. To compare complications and reoperation rates during the 5-year period after surgery between patients who have undergone lumbar spine fusion surgery and those who have undergone laminectomy or discectomy alone. Spinal fusion is associated with wider surgical exposure, more extensive dissection, and longer operative times than lumbar surgery without fusion, and previous studies have shown higher complication rates and hospital charges associated with these more complex procedures. In elderly patients, spinal fusion operations were associated with higher mortality rates than laminectomy or discectomy alone, and reoperation rates were not lower. In the current study, reoperations, mortality, and complications following lumbar spine surgery were examined for the general population. A statewide hospital discharge database was used to identify all Washington patients who underwent spine surgery in 1988 and to determine the rate of reoperation during the subsequent 5 years. Administrative records also were used to identify complications, mortality, and hospital charges associated with the operations. Unadjusted complication and reoperation rates for the groups were compared using chi-square statistics. Adjusted rates were compared using logistic regression and proportional hazards (Cox) regression after controlling for age, gender, prior spine surgery, diagnosis, comorbidity, type of surgery, and coverage by Workers' Compensation. Of 6376 patients who underwent lumbar surgery for degenerative conditions in Washington in 1988, 1041 (16%) had operations involving spine fusion. Diagnoses of degenerative disc disease or possible instability were more frequent among patients undergoing fusion surgery, whereas herniated discs were more frequent among those undergoing discectomy or laminectomy alone. Complications were recorded in 18% of fusion patients and 7% of nonfusion patients (P < 0.01), but mortality rates did not differ. Unadjusted reoperation rates over the 5-year period were greater for patients who underwent fusion than for patients who underwent nonfusion surgery (18% vs. 15%, respectively), but after adjustment for baseline characteristics, fusion patients had only a slightly greater (and nonsignificant) risk of reoperation (relative risk 1.1, confidence interval .9-1.3). As in previous studies, complications in the current study occurred more frequently among patients who underwent lumbar spine fusion than among those who underwent laminectomy or discectomy alone. Reoperations were at least as frequent after fusion, but the authors could not assess treatment efficacy in terms of pain relief or improved function. Although the characteristics of patients undergoing fusion differed from those undergoing a laminectomy or discectomy alone, there appeared to be sufficient overlap in the clinical populations to warrant closer scrutiny of the safety, efficacy, and indications for spinal fusions, preferably in randomized trials.

Evaluating sources of traumatic spinal cord injury surveillance data in Colorado.

The purpose of this study is to evaluate the sources reporting hospitalized spinal cord injury cases to the statewide, population-based surveillance system in Colorado for the year 1994. Three reporting sources were evaluated: clinical contact persons, medical records departments, and a centralized statewide hospital discharge database. Two evaluation strategies were utilized; these include both measures of accuracy and estimates of missed cases. For the latter, capture-recapture techniques were used to estimate the number of hospitalized spinal cord injury cases missed by all three reporting sources. The clinical contact persons reported 84 confirmed cases, missed 80 confirmed cases, and reported 10 cases that were later determined not to have spinal cord injuries, resulting in a sensitivity of 0.51. Medical records departments and the discharge database reported 143 and 147 cases, respectively, missed 21 and 17 confirmed cases, and reported 118 and 69 cases that were later determined not to be cases of hospitalized injuries of the spinal cord, resulting in sensitivities of 0.87 and 0.90. Capture-recapture results indicate all three sources combined missed an estimated 1-5 cases, yielding a total annual incidence rate for hospitalized spinal cord injury ranging from 45.1 to 46.3 per million population.

Correlates of cochlear implantation, 1986-1992.

There is a paucity of information regarding the use of cochlear implants within large populations. This article describes correlates of cochlear implantation procedures using a statewide hospital discharge database. Among the 146 implant procedures, 55% involved female patients, whereas the largest groups of patients were represented by younger and older persons (27% between ages 2 and 9 years and 24% 60 years and older). A bimodal distribution was apparent for average annual age-specific rates of cochlear implantation, with the highest rates among persons aged 2 to 9 years (5.4 implants per 1 million) and persons aged 60 to 69 years (3.7 implants per 1 million). Total hospital charges, excluding professional fees, exceeded $12,000 per implant and were found to vary significantly when examined by length of stay and by calendar year of procedure. The data presented are unique with regard to the total number of cochlear implant procedures included and the large, diverse population used. This study expands knowledge concerning the epidemiology and utilization of cochlear implantation.

Correlates of cochlear implantation, 1986-1992

There is a paucity of information regarding the use of cochlear implants within large populations. This article describes correlates of cochlear implantation procedures using a statewide hospital discharge database. Among the 146 implant procedures, 55% involved female patients, whereas the largest groups of patients were represented by younger and older persons (27% between ages 2 and 9 years and 24% 60 years and older). A bimodal distribution was apparent for average annual age-specific rates of cochlear implantation, with the highest rates among persons aged 2 to 9 years (5.4 implants per 1 million) and persons aged 60 to 69 years (3.7 implants per 1 million). Total hospital charges, excluding professional fees, exceeded $12,000 per implant and were found to vary significantly when examined by length of stay and by calendar year of procedure. The data presented are unique with regard to the total number of cochlear implant procedures included and the large, diverse population used. This study expands knowledge concerning the epidemiology and utilization of cochlear implantation. (Otolaryngol Head Neck Surg 1996;114:22-6.)

Hospital Admissions of HIV-Infected Patients from 1988 to 1992 in Maryland

To determine how the patterns of inpatient hospital care for HIV-infected patients have evolved in recent years, we analyzed data obtained from a statewide hospital discharge database from Maryland for the years 1988, 1990, and 1992. For each of these years, we compared demography, diagnoses, lengths of stay, use of the intensive care unit, third-party payer, and hospital charges (inflation-adjusted to 1992 dollars). HIV-infected patients accounted for 0.42% of all Maryland's hospital admissions in 1988, 0.68% in 1990, and 1.1% in 1992, with progressively more women and African-Americans hospitalized. Average lengths of stay fell from 11.7 days (1988) to 10.7 days (1990) and 9.5 days (1992) (p < 0.0001). Average charges per admission fell from $11,634 (1988) to $9,938 (1990) and $8,618 (1992) (p < 0.0001). Medicare or Medicaid paid for 50.9% of hospital admissions in 1988, 56.8% in 1990, and 66.8% in 1992 (p < 0.001). In-hospital mortality rates (7.8% in 1988, 7.9% in 1990, and 7.7% in 1992; p = 0.783) were stable, as was severity of illness. P. carinii pneumonia (PCP) was the most common principal diagnosis, but it declined in prevalence from 13.6% in 1988 to 9.1% in 1992 (p < 0.0001). Principal diagnoses of other opportunistic infections remained stable (8.0% in 1988, 9.9% in 1990, 8.6% in 1992; p = 0.90), as did other nonopportunistic infections (32.8% in 1988, 27.2% in 1990, and 30.0% in 1992; p = 0.16). Non-PCP pneumonias increased from 7.6% (1988) to 10.2% (1992) (p < 0.0001). Substance abuse as a principal or secondary diagnosis increased from 30.9% (1988) to 34.3% (1992) (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

INCIDENCE, MANAGEMENT, AND OUTCOME OF FEMORAL SHAFT FRACTURE

Early surgical management of femoral shaft fracture (FSF) is considered the standard but patients are still treated nonsurgically. The purpose of this study was to analyze the results of management of FSF in a large population based data base. Data were obtained from a statewide hospital discharge data base for 1989-1992. Adults having a FSF were stratified by ISS (ISS < 15 vs. ISS > or = 15) and management (nonsurgical, surgery within 1 day, surgery at 2-4 days, or surgery at > 4 days). Mortality rates and mean length of hospital stay were compared among groups. 2805 patients had FSFs: 69% were managed surgically and 31% nonsurgically. Mortality was higher for nonsurgical therapy in both ISS groups. In the surgically treated groups, length of hospitalization increased as delay to surgery increased. In patients with an ISS > or = 15, repair at 2-4 days was associated with the lowest mortality and shortest hospitalization, while a trend to higher mortality and longer hospitalization was noted with repair within 1 day. 31% of patients were treated nonsurgically with higher associated mortality. These results support "early" surgical fixation, which can shorten hospital stay without increasing mortality regardless of overall injury severity. The trend toward higher mortality in severely injured patients operated on within 1 day of admission suggests that this group warrants further study and individualized management.

The Maine Women's Health Study: I. Outcomes of hysterectomy.

To assess the effect of hysterectomy for nonmalignant conditions on symptoms and quality of life and to identify adverse effects 1 year after surgery. The Maine Women's Health Study was a prospective cohort study of 418 women ages 25-50 years undergoing hysterectomy for any nonmalignant condition. Patients recruited from the practices of 63 physicians performing hysterectomy throughout Maine were interviewed at the time of surgery and 3, 6, and 12 months later. Clinical and hospitalization data were obtained from physician reports and from a statewide hospital discharge data base. The primary outcomes of interest were symptom relief, changes in quality of life, and the development of new symptoms or problems during the year following surgery. The most frequent indications for hysterectomy were leiomyomas (35%), abnormal bleeding (22%), and chronic pelvic pain (18%). For these indications, hysterectomy resulted in marked improvements in a range of symptoms, including pelvic pain, urinary symptoms, fatigue, psychological symptoms, and sexual dysfunction. Significant improvements in scores for indices of mental health, general health, and activity were evident at 6 months and sustained at 1 year. New problems after hysterectomy (measured in those free of the symptom preoperatively) included hot flashes (13%), weight gain (12%), depression (8%), and lack of interest in sex (7%). Hysterectomy is highly effective for relief of symptoms associated with common nonmalignant gynecologic conditions. Symptom relief following hysterectomy is associated with a marked improvement in quality of life. New problems are reported after hysterectomy by a limited number of women.

Readmission after surgery in Washington State rural hospitals.

Because of concern about the quality of care in rural hospitals, we examined readmission following four surgical procedures commonly performed in Washington State rural hospitals: appendectomy, cesarean section, cholecystectomy, and transurethral prostatectomy. In a retrospective cohort study, we identified all patients discharged after receiving one of the foregoing procedures using the statewide hospital discharge database. Readmissions to any hospital in the state within 7 or 30 days of discharge were also identified. During the 2-year period examined, there were no significant differences in readmission rates for surgeries performed in rural and urban hospitals, although the readmission rates for all four procedures were nominally lower in rural hospitals. Logistic regression analyses that controlled for factors that influence readmission did not change these results. Investigating readmission rates following common surgeries, we found no evidence of low-quality surgical care in Washington State rural hospitals. Early readmission is an imperfect marker for poor surgical outcome, however, and other proxies for quality remain to be examined.

Improvement in AIDS Case Reporting, South Carolina

To the Editor. — Earlier this year we commented in a letter toThe Journal 1 about the reporting of acquired immunodeficiency syndrome (AIDS) cases in South Carolina before the state implemented an active surveillance program (previous to July 1987). In the 18-month study period prior to an active surveillance program, Conway et al 2 found 59.5% reporting of AIDS cases. We have completed an analysis of AIDS case reporting in the subsequent 18 months during which active surveillance was started in South Carolina (July 1, 1987, through December 31, 1988), using the same methodology as Conway et al, a computerized search of a statewide hospital discharge database combined with chart review. During this 18-month period, 181 cases identified on the statewide hospital discharge database met the 1987 Centers for Disease Control AIDS case definition. Of the 181 cases, 159 (88%) had been reported to the South Carolina AIDS registry