Background-Multiple studies have demonstrated a consistent association between ambient particulate air pollution and increased risk of hospital admissions and deaths for cardiovascular causes. We investigated the associations between fine particulate pollution (PM 2.5 ) and blood pressure during 631 repeated visits for cardiac rehabilitation in 62 Boston residents with cardiovascular disease. Methods and Results-Blood pressure, cardiac risk factor, and exercise data were abstracted from records of rehabilitation visits between 1999 and 2001. We applied mixed-effect models, controlling for body mass index, age, gender, number of visits, hour of day, and weather variables. For an increase from the 10th to the 90th percentile in mean PM 2.5 level during the 5 days before the visit (10.5 g/m 3 ), there was a 2.8-mm Hg (95% CI, 0.1 to 5.5) increase in resting systolic, a 2.7-mm Hg (95% CI, 1.2 to 4.3) increase in resting diastolic, and a 2.7-mm Hg (95% CI, 1.0 to 4.5) increase in resting mean arterial blood pressure. The mean PM 2.5 level during the 2 preceding days (13.9 g/m 3 ) was associated with a 7.0-mm Hg (95% CI, 2.3 to 12.1) increase in diastolic and a 4.7-mm Hg (95% CI, 0.5 to 9.1) increase in mean arterial blood pressure during exercise in persons with resting heart rate Ն70 bpm, but it was not associated with an increase in blood pressure during exercise in persons with heart rate Ͻ70 bpm. Conclusions-In patients with preexisting cardiac disease, particle pollution may contribute to increased risk of cardiac morbidity and mortality through short-term increases in systemic arterial vascular narrowing, as manifested by increased peripheral blood pressure.
Fatigue, a complex symptom, significantly affects the quality of life in many patients with systemic lupus erythematosus (SLE). To understand this phenomenon, 23 patients with SLE and fatigue were studied. Standardized tests of depression (NIMH), fatigue, exercise tolerance (ETT) on a bicycle ergometer, and SLE activity were obtained. At baseline, SLE patients had significantly lower maximum oxygen consumption (VO2 max) than normals (p less than 0.005). Adjusted for age and sex, SLE patients perform at 54% of their expected maximum VO2, which is similar to published data from patients with rheumatoid arthritis. Depression by NIMH was not correlated with VO2 max or length of time on ETT. Fatigue measured by Profile of Mood States (POMS) was correlated with ETT time (r = 0.476, p less than 0.025) and with VO2 max (r = -0.402, p less than 0.07). After an 8-week aerobic conditioning programme the experimental group increased their aerobic capacity by 19% in contrast to 8% in controls. This change correlated with decreased fatigue as measured by visual analogue scales. Exercise did not exacerbate disease, and only two of 16 experimental subjects experienced transient joint symptoms during exercise.
Despite large gains in the medical and surgical treatment of angina pectoris in the past two decades, many patients are refractory to conventional medical therapy and are unsuitable for a first or, more commonly, repeat coronary revascularization procedure. We evaluated the efficacy of perhexiline maleate, a drug with an antianginal mechanism of action in humans that is as yet unknown, by using a randomized double-blind placebo-controlled crossover design in 17 patients with refractory angina who continued to receive maximal antianginal therapy, typically including nitrates, a ,B-blocker, and a calcium channel antagonist. In view of perhexiline's potential for hepatic and neurological toxicity, plasma drug levels were monitored and maintained in the 150-600 ng/ml range. Sixty-three percent of patients were judged perhexiline responders by objective exercise testing criteria, as compared with 18% of patients on placebo (p<0.05). By blinded review of subjective measures of anginal frequency and severity, 65% of patients noted an improvement while on perhexiline, whereas no patient identified the placebo phase with improvement. Side effects observed in 29% of patients were minor and related to transient elevations of blood levels of more than 600 ng/ml; no patient suffered hemodynamic or cardiac conduction abnormalities attributable to perhexiline. With attention to the pharmacokinetics of perhexiline's elimination in individual patients, this novel antianginal agent seems to be safe and effective and deserves further evaluation in patients already receiving maximal antianginal therapy who are not candidates for revascularization procedures. (Circulation 1990;81:1260-1270
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.