Scientific
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OBJECTIVE: This study was conducted to determine if type 1 diabetes is associated with an increased risk of fracture across the life span. RESEARCH DESIGN AND METHODS: This population-based cohort study used data from The Health Improvement Network (THIN) in the U.K. (data from 1994 to 2012), in which 30,394 participants aged 0-89 years with type 1 diabetes were compared with 303,872 randomly selected age-, sex-, and practice-matched participants without diabetes. Cox regression analysis was used to determine hazard ratios (HRs) for incident fracture in participants with type 1 diabetes. RESULTS: A total of 334,266 participants, median age 34 years, were monitored for 1.9 million person-years. HR were lowest in males and females age <20 years, with HR 1.14 (95% CI 1.01-1.29) and 1.35 (95% CI 1.12-1.63), respectively. Risk was highest in men 60-69 years (HR 2.18 [95% CI 1.79-2.65]), and in women 40-49 years (HR 2.03 [95% CI 1.73-2.39]). Lower extremity fractures comprised a higher proportion of incident fractures in participants with versus those without type 1 diabetes (31.1% vs. 25.1% in males, 39.3% vs. 32% in females; P < 0.001). Secondary analyses for incident hip fractures identified the highest HR of 5.64 (95% CI 3.55-8.97) in men 60-69 years and the highest HR of 5.63 (95% CI 2.25-14.11) in women 30-39 years. CONCLUSIONS: Type 1 diabetes was associated with increased risk of incident fracture that began in childhood and extended across the life span. Participants with type 1 diabetes sustained a disproportionately greater number of lower extremity fractures. These findings have important public health implications, given the increasing prevalence of type 1 diabetes and the morbidity and mortality associated with hip fractures.

BACKGROUND: Boils and abscesses are common in primary care but the burden of recurrent infection is unknown. AIM: To investigate the incidence of and risk factors for recurrence of boil or abscess for individuals consulting primary care. DESIGN AND SETTING: Cohort study using electronic health records from primary care in the UK. METHOD: The Health Improvement Network (THIN) database was used to identify patients who had consulted their GP for a boil or abscess. Poisson regression was used to examine the relationship between age, sex, social deprivation, and consultation and to calculate the incidence of, and risk factors for, repeat consultation for a boil or abscess. RESULTS: Overall, 164 461 individuals were identified who consulted their GP for a boil or abscess between 1995 and 2010. The incidence of first consultation for a boil or abscess was 512 (95% CI = 509 to 515) per 100 000 person-years in females and 387 (95% CI = 385 to 390) per 100 000 person-years in males. First consultations were most frequent in younger age groups (16-34 years) and those with the greatest levels of social deprivation. The rate of repeat consultation for a new infection during follow up was 107.5 (95% confidence interval [CI] = 105.6 to 109.4) per 1000 person-years. Obesity (relative risk [RR] 1.3, 95% CI = 1.2 to 1.3), diabetes (RR 1.3, 95% CI = 1.2 to 1.3), smoking (RR 1.3, 95% CI = 1.2 to 1.4), age <30 years (RR 1.2, 95% CI = 1.2 to 1.3), and prior antibiotic use (RR 1.4, 95% CI = 1.3-1.4) were all associated with repeat consultation for a boil or abscess. CONCLUSION: Ten percent of patients with a boil or abscess develop a repeat boil or abscess within 12 months. Obesity, diabetes, young age, smoking, and prescription of an antibiotic in the 6 months before initial presentation were independently associated with recurrent infection, and may represent options for prevention.

BACKGROUND: The use of antithrombotic drugs (anticoagulants and antiplatelet drugs) has been reported to increase the risk of hemorrhagic stroke (HS) relative to no treatment. This study was performed to characterize the incidence and predictors of HS in users of acetylsalicylic acid (ASA) for the secondary prevention of cardiovascular events. METHODS: A cohort of 36,775 ASA users aged 50-84 years in 2000-2007 was identified from The Health Improvement Network database. The incidence of HS was calculated, and a nested case-control analysis, adjusted for potential confounding factors, was performed to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for the association of potential risk factors with HS in current users of ASA. RESULTS: The overall incidence of HS was 5.70 cases per 10,000 person-years and increased with age. In current ASA users, the incidence of HS was 4.91 cases per 10,000 person-years. Predictors of HS in patients taking ASA for secondary prevention included a history of HS (OR, 4.84; 95% CI, 1.48-15.88), a history of atrial fibrillation (OR, 4.03; 95% CI, 1.53-10.62), and hypnotic/anxiolytic drug use (OR, 2.67; 95% CI, 1.17-6.05). The small number of patients using warfarin also had an increased risk of HS (OR, 23.42; 95% CI, 4.89-112.10). CONCLUSIONS: Physicians should consider additional risk factors for HS, such as a history of HS or atrial fibrillation, and the use of warfarin, before prescribing ASA for the secondary prevention of cardiovascular events.

OBJECTIVE: The goal of the study was to determine whether complications of diabetes well-known to be associated with death such as cardiovascular disease and renal failure fully explain the higher rate of death in those who have undergone a lower-extremity amputation (LEA). RESEARCH DESIGN AND METHODS: This was a longitudinal cohort study of patients cared for in the Health Improvement Network. Our primary exposure was LEA and outcome was all-cause death. Our "risk factor variables" included a history of cardiovascular disease (a history of myocardial infarctions, cerebrovascular accident, and peripheral vascular disease/arterial insufficiency), Charlson index, and a history of chronic kidney disease. We estimated the effect of LEA on death using Cox proportional hazards models. RESULTS: The hazard ratio (HR) for death after an LEA was 3.02 (95% CI 2.90, 3.14). The fully adjusted (all risk factor variables) LEA HR was diminished only by ∼22% to 2.37 (2.27, 2.48). Furthermore, LEA had an area under the receiver operating curve (AUC) of 0.51, which is poorly predictive, and the fully adjusted model had an AUC of 0.77, which is better but not strongly predictive. Sensitivity analysis revealed that it is unlikely that there exists an unmeasured confounder that can fully explain the association of LEA with death. CONCLUSIONS: Individuals with diabetes and an LEA are more likely to die at any given point in time than those who have diabetes but no LEA. While some of this variation can be explained by known complications of diabetes, there remains a large amount of unexplained variation.