Myocardial infarction and peripheral arterial disease: Treatment patterns and long-term outcome in men and women results from a Swedish nationwide study.

BACKGROUND: Differences in comorbidity, pharmacotherapy, cardiovascular (CV) outcome, and mortality between myocardial infarction (MI) patients and peripheral arterial disease (PAD) patients are not well documented. AIM: The aim of this study was to compare comorbidity, treatment patterns, CV outcome, and mortality in MI and PAD patients, focusing on sex differences. METHODS: This observational, population-based study used data retrieved from mandatory Swedish national registries. The risks of MI and death were assessed by Kaplan-Meier analysis. Secondary preventive drug use was characterized. Cox proportional risk hazard modelling was used to determine the risk of specific events. RESULTS: Overall, 91,808 incident MI patients and 52,408 PAD patients were included. CV mortality for MI patients at 12, 24, and 36 months after index was 12.3%, 19.3%, and 25.4%, and for PAD patients it was 15.5%, 23.4%, and 31.0%. At index, 89% of MI patients and 65% of PAD patients used aspirin and 74% and 53%, respectively, used statins. Unlike MI women, women with PAD had a lower rate of other CV-related comorbidities and a lower risk of CV events (age-adjusted hazard ratio 0.81, 95% confidence interval 0.79‒0.84), CV death (0.78, 0.75‒0.82), and all-cause death (0.78, 0.76‒0.80) than their PAD male counterparts. CONCLUSION: PAD patients were less intensively treated and had a higher CV mortality than MI patients. Women with PAD were less likely than men to present with established polyvascular disease, whereas the opposite was true of women with MI. This result indicates that the lower-limb vasculature may more often be the index site for atherosclerosis in women.

Amputation Rates, Mortality, and Pre-operative Comorbidities in Patients Revascularised for Intermittent Claudication or Critical Limb Ischaemia: A Population Based Study.

OBJECTIVES: The aims of this population based study were to describe mid- to long-term amputation risk, cumulative incidence of death or amputation, and differences in pre-operative comorbidities in patients revascularised for lower limb peripheral artery disease (PAD). METHODS: This was an observational cohort study. Data from the Swedish National Quality Registry for Vascular Surgery (Swedvasc) were combined with mandatory national health care registries and patient medical records. All patients who underwent revascularisation in Sweden between May 2008 and May 2013 for intermittent claudication (IC) or critical limb ischaemia (CLI), aged 50 years and older, were identified through the Swedvasc database. The mandatory national health care registries and medical records provided data on comorbidities, mortality, and major amputations. RESULTS: A total of 16,889 patients with PAD (IC, n = 6272; CLI, n = 10,617) were studied. The incidence of amputations in IC patients was 0.4% (range 0.3%-0.5%) per year. Among CLI patients, the amputation rate during the first 6 months following revascularisation was 12.0% (95% CI 11.3-12.6). Thereafter, the incidence declined to approximately 2% per year. The cumulative combined incidence of death or amputation 3 years after revascularisation was 12.9% (95% CI 12.0-13.9) in IC patients and 48.8% (95% CI 47.7-49.8) in CLI patients. Among CLI patients, compared with IC patients, the prevalence of diabetes, ischaemic stroke, heart failure, and atrial fibrillation was approximately doubled and renal failure was nearly tripled, even after age standardisation. CONCLUSION: The risk of amputation is particularly high during the first 6 months following revascularisation for CLI. IC patients have a benign course in terms of limb loss. Mortality in both IC and CLI patients is substantial. Revascularised CLI patients have different comorbidities from IC patients.

The Risk of Disease Progression in Peripheral Arterial Disease is Higher than Expected: A Meta-Analysis of Mortality and Disease Progression in Peripheral Arterial Disease.

OBJECTIVE: Peripheral arterial disease (PAD) afflicts up to 20% of older people and is associated with a high risk of cardiovascular (CV) morbidity, but a rather low risk of progression of leg symptoms. These risk estimations are largely taken from cohort studies performed 20 years ago. To test the validity of this, available data were systematically reviewed and attempts were made to perform meta-analyses of CV risk and disease progression. METHODS: A database literature search was conducted of the period 1990-2015 using related subject headings. Inclusion criteria were cohort studies for PAD, sample size >100 subjects, follow up time ≥1 year, and studies presenting endpoints covering mortality and/or CV events. Analyses were performed for a reference population, as well as groups with asymptomatic PAD (APAD), symptomatic PAD, and subjects with ankle brachial index <0.9. RESULTS: Of 354 identified articles, 35 were eligible for systematic review. Sample size varied between 109 and 16,440 subjects. Mean age in the cohorts ranged from 56 to 81 years (SD 10.8) and mean follow up was 6.3 years (range 1-13). Most included patients with symptomatic PAD had IC (91%). Symptomatic PAD subjects had higher 5 year cumulative CV mortality than the reference population, 13% versus 5%. During follow up, approximately 7% of APAD patients progressed to IC, and 21% of IC patients were diagnosed as having critical limb ischemia, with 4-27% undergoing amputations. CONCLUSION: The risk to the limb is underestimated in PAD patients, whereas the CV related morbidity is more moderate than stated in the guidelines. The latter observation is especially valid for IC patients. These findings should be considered when evaluating patients for treatment.

Asymptomatic peripheral arterial disease: is pharmacological prevention of cardiovascular risk cost-effective?

Peripheral arterial disease (PAD) is associated with an increased risk of early death in cardiovascular (CV) disease. The majority of PAD subjects are asymptomatic with a prevalence of 11 per cent among the elderly. Long-term drug prevention aiming to minimize disease progression and CV events in these subjects is probably beneficial, but expensive. The purpose of this analysis was to evaluate the cost-effectiveness of pharmacological risk reduction in subclinical PAD. Long-term costs and quality-adjusted life years (QALYs) were estimated by employing a decision-analytic model for ACE-inhibitor, statin, aspirin and non-aspirin anti-platelet therapy. Rates of CV events without treatment were derived from epidemiological studies and event rate reduction were retrieved from clinical trials. Costs and health-related quality of life estimates were obtained from published sources. All four drugs reduced CV events. Using ACE-inhibition resulted in a heart rate (HR) of 0.67 (95% CI: 0.55-0.79), statins 0.74 (0.70-0.79), and clopidogrel 0.72 (0.43-1.00). Aspirin had a HR of 0.87 and the 95% CI passed included one (0.72-1.03). ACE-inhibition was associated with the largest reduction in events leading to the highest gain in QALYs (7.95). Furthermore, ACE-inhibitors were associated with the lowest mean cost €40.556. In conclusion, while all drugs reduced CV events, ACE-inhibition was the most cost-effective. These results suggest that we should consider efforts to identify patients with asymptomatic PAD and, when identified, offer ACE-inhibition.