Marc D. Silverstein

Benign Positional Vertigo: Incidence and Prognosis in a Population-Based Study in Olmsted County, Minnesota

A retrospective review of our population-based medical records linkage system for residents of Olmsted County, Minnesota, revealed 53 patients (34 women and 19 men; mean age, 51 years) with newly diagnosed benign positional vertigo in 1984. The age- and sex-adjusted incidence was 64 per 100,000 population per year (95% confidence interval, 46 to 81 per 100,000). The incidence of benign positional vertigo increased by 38% with each decade of life (95% confidence interval, 23 to 54%). One patient had an initial stroke during follow-up; thus, the relative risk for new stroke associated with benign positional vertigo was 1.62 (95% confidence interval, 0.04 to 8.98) in comparison with the expected occurrence based on incidence rates for an age- and sex-adjusted control population. The observed survival among the 53 Olmsted County residents with benign positional vertigo diagnosed in 1984 was not significantly different from that of an age- and sex-matched general population. Patients with benign positional vertigo seem to have a good prognosis.

Allergic rhinitis in Rochester, Minnesota residents with asthma: Frequency and impact on health care charges ☆ ☆☆ ★

BACKGROUNDnAsthma is a common and costly condition. Concomitant asthma and allergic rhinitis (AR) have been shown to increase the medication costs for people with asthma. No studies have compared medical care costs of those with and without concomitant AR.nnnOBJECTIVESnWe sought to determine the prevalence and incremental medical care costs of concomitant AR.nnnMETHODSnFor each member of a population-based asthma cohort, we used all their medical charts within Olmsted County to record age at first diagnosis of asthma; the presence and age of any diagnosis of AR; and the total, ambulatory, and respiratory care-related costs of medical care. Costs were compared for age- and sex-specific strata of people with asthma who did and did not have AR.nnnRESULTSnAR was most commonly diagnosed in people whose asthma was diagnosed before age 25 (prevalence of 59%) and uncommonly diagnosed in anyone after age 40 (prevalence <15%). Yearly medical care charges were on average 46% higher for those with asthma and concomitant AR than for persons with asthma alone, controlling for age and sex. We were unable to assess the impact of treatment of AR on medical care charges.nnnCONCLUSIONSnPhysicians should consider the diagnosis of AR (prevalence >50%) in all symptomatic children and young adults with asthma. Further evaluation is necessary to evaluate the ability of treatment to decrease the incremental costs of AR in persons with asthma.

Predictors of Outcome After Percutaneous Endoscopic Gastrostomy: A Community-Based Study

Percutaneous endoscopic gastrostomy (PEG) is used to provide nutrition for patients who are unable to eat but have a functionally intact gut. Clinical guidelines for PEG are uncertain and have been derived mainly from referral practices. We performed a population-based cohort study in 97 residents of Olmsted County, Minnesota, referred for PEG between January 1982 and December 1988 to determine complications, duration of tube feeding, and survival. Follow-up continued until death or February 1990. Inpatient and outpatient records were reviewed to determine indications, comorbid conditions, level of consciousness, and limitations in activities of daily living. Outcomes determined after referral for PEG included type and number of complications, tube removal, and survival. Statistical methods used included Kaplan-Meier and proportional hazards regression analyses. PEG placement was successful in 94% of patients. Although complications occurred in 70% of patients, they usually were minor (88%) and most occurred within 3 months. In 24 patients, tubes were removed because eating was resumed. The probability of surviving 30 days, 1.5 years, and 4 years after referral for PEG was 78%, 35%, and 27%, respectively. The major causes of death within and after 30 days were pneumonia, heart disease, and vascular disease of the central nervous system. An increased risk of death after referral for PEG placement was associated with older age, male gender, diabetes, and specific indications for PEG. If validated in other population-based studies, these predictors of survival after referral for PEG placement could be used to identify patients with a low probability of survival who may not benefit from PEG.

Attained adult height after childhood asthma: Effect of glucocorticoid therapy

BACKGROUNDnAlthough oral and inhaled glucocorticoid therapy may impair growth in children with asthma, the effect of glucocorticoid therapy and asthma on attained adult height has not been extensively studied in representative children in the community.nnnOBJECTIVESnThe study was designed to compare the attained adult height of children with asthma with the attained adult height of nonasthmatic children and to compare the attained adult height of asthmatic children treated with glucocorticoids with the attained adult height of asthmatic children who did not receive glucocorticoids.nnnMETHODSnResidents of Rochester, Minnesota, with onset of asthma from 1964 to 1987 and age- and sex-matched non-asthmatic residents of Rochester were studied. Glucocorticoid exposure was assessed from medical records. The mean of 5 stadiometer measurements of adult height, adjusted for sex and parental height, was analyzed.nnnRESULTSnOne hundred fifty-three patients with asthma (mean age at onset, 6.1 +/- 4.8 years) and 153 age- and sex-matched nonasthmatic subjects were studied. Adult height of patients with asthma (mean age at measurement, 25.7 +/- 5.2 years) was not significantly different from the adult height of non-asthmatic subjects; the overall difference, adjusted for mid-parental height, was -0.20 cm (95% confidence interval from -0.27 to 1.64). The adult height of asthmatic children treated with glucocorticoids was not significantly different from the adult height of patients with asthma not treated with glucocorticoids; the difference after adjusting for mid-parental height was -0.2 cm (95% confidence interval from -0.1 to 0.6).nnnCONCLUSIONSnWe conclude that the attained adult height of patients with asthma is not different from the adult height of age- and sex-matched nonasthmatic subjects and that the attained adult height of asthmatic children treated with glucocorticoids is not significantly different from the adult height of children not treated with glucocorticoids.

Risk factors for 30-day hospital readmission in patients ≥65 years of age

The objective of the study was to develop and validate predictors of 30-day hospital readmission using readily available administrative data and to compare prediction models that use alternate comorbidity classifications. A retrospective cohort study was designed; the models were developed in a two-thirds random sample and validated in the remaining one-third sample. The study cohort consisted of 29,292 adults aged 65 or older who were admitted from July 2002 to June 2004 to any of seven acute care hospitals in the Dallas–Fort Worth metropolitan area affiliated with the Baylor Health Care System. Demographic variables (age, sex, race), health system variables (insurance, discharge location, medical vs surgical service), comorbidity (classified by the Elixhauser classification or the High-Risk Diagnoses in the Elderly Scale), and geographic variables (distance from patients residence to hospital and median income) were assessed by estimating relative risk and risk difference for 30-day readmission. Population-attributable risk was calculated. Results showed that age 75 or older, male sex, African American race, medical vs surgical service, Medicare with no other insurance, discharge to a skilled nursing facility, and specific comorbidities predicted 30-day readmission. Models with demographic, health system, and either comorbidity classification covariates performed similarly, with modest discrimination (C statistic, 0.65) and acceptable calibration (Hosmer-Lemeshow ϰ2 = 6.08; P > 0.24). Models with demographic variables, health system variables, and number of comorbid conditions also performed adequately. Discharge to long-term care (relative risk, 1.94; 95% confidence interval, 1.80–2.09) had the highest population-attributable risk of 30-day readmission (12.86%). A 25% threshold of predicted probability of 30-day readmission identified 4.1% of patients ≥65 years old as priority patients for improved discharge planning. We conclude that elders with a high risk of 30-day hospital readmission can be identified early in their hospital course.

Venous Thromboembolism Associated With Hip and Knee Arthroplasty: Current Prophylactic Practices and Outcomes

Joint registry and hospital data bases for 5,024 total hip and total knee arthroplasties done between 1986 and 1988 at the Mayo Clinic were used to study prophylactic measures and frequency of symptomatic deep venous thrombosis and pulmonary embolism. In virtually all patients, graduated compression stockings were used, with or without another type of prophylaxis. Only 44 of 3,115 patients who underwent hip arthroplasty (1.4%) and 32 of 1,909 patients who underwent knee arthroplasty (1.7%) had definite or probable deep venous thrombosis or pulmonary embolism. Death definitely or possibly attributable to pulmonary embolism occurred in 11 patients who underwent hip arthroplasty (0.35%) and 1 patient who underwent knee arthroplasty (0.05%). Although patients with a history of deep venous thrombosis or pulmonary embolism were more likely to receive warfarin than were patients without such a history, the relative risk of symptomatic deep venous thrombosis or pulmonary embolism in patients who underwent hip arthroplasty and received warfarin postoperatively was approximately half that in patients who received other types of prophylaxis. The risk of death from pulmonary embolism was similarly diminished in the group that received warfarin. The lower rates of these complications in the patients who received warfarin support the prophylactic use of this agent after total hip arthroplasty.

Impact of clinical preventive services in the ambulatory setting

Indicators of the performance of clinical preventive services (CPS) have been adopted in the ambulatory setting to improve quality of care. The impact of CPS was evaluated in a network of 49 primary care practices providing care to an estimated 245,000 adults in the Dallas–Fort Worth area through a sample chart review to determine delivery of recommended evidence-based CPS combined with medical literature estimates of the effectiveness of CPS. In this population in 2005, CPS were estimated to have prevented 36 deaths and 97 incident cases of cancer; 420 coronary heart disease events (including 66 sudden deaths) and 118 strokes; 816 cases of influenza and pneumonia (including 24 hospital admissions); and 87 osteoporosis-related fractures. Thus, CPS have substantial benefits in preventing deaths and illness episodes.