Seasonal Variation and Trends in Heart Failure Morbidity and Mortality in a South American Community Hospital

Abstract

Circannual variation in cardiovascular events is well-known. Seasonal variation (SV) in heart failure (HF) has been described in the Northern Hemisphere, but there is scarcity of data in South America. The goals of the present study were to (1) describe the SV of admissions and deaths for HF, and (2) describe trends in HF morbidity and mortality in a community hospital in Argentina from 1992 to 1999. The study sample included 6369 admissions. During this period, the number of HF admissions rose by 188% and the rate HF admissions/all admissions increased from 3.28% to 7.84%. In-hospital mortality decreased from 21% to 13%. HF admissions followed a seasonal pattern with a winter-spring predominance. Male and very old patients were the subgroups with the highest SV. The authors identified clear SV in HF deaths and admissions, which raises a different hypothesis about the rationale of HF admissions and provides information for the organization of care and resource allocation.

Seasonal Variation in Hospital Admission in Patients with Heart Failure and Its Effect on Prognosis

“…This finding has been well described in the literature and is a global phenomenon described in the Northern [2,3,4,5,6,8,12] as well as the Southern hemisphere [7,13]. This seasonal variation is particularly seen in the elderly [3,5,7]. The postulated reasons for this are the increased occurrence of ischemic events in the winter [14] as well as the increased occurrence of infections during this period [3].…”

“…Patients with HF are frequently hospitalized and there is a significant mortality in the first year after admission [1]. A seasonal variation in hospital admissions in patients with HF has been described [2,3,4,5,6,7,8], with most admissions occurring in the winter season. The increased hospitalization during the winter months is perceived to be due to increased ischemia [9,10], hypertension [11] and intercurrent infections [3], all related to the colder climate.…”

The seasonality in heart failure deaths and total cardiovascular deaths

“…1 Winter increases in heart failure (HF) admissions have been found in France, 2 Spain, 3 Scotland, 4 Japan, 5 and Argentina. 8 In France, HF deaths were 20% above average in January and 15% below average in August. 2 In Madrid, HF hospitalisations were 25% above average in January and 33% below average in August.…”

Sazonalidade, efemérides e a mortalidade por doença coronariana, AVC, insuficiência cardíaca, acidente de transporte, suicídio e homicídio na cidade de São Paulo, 1996 a 2009

“…O maior aumento durante o inverno ocorreu para o grupo de insuficiência cardíaca (Barnett et al, 2008). O mesmo padrão com maior incidência de mortes por insuficiência cardíaca no inverno foi relatada na Argentina (Diaz et al, 2007).…”

“…O mesmo padrão foi encontrado em diferentes localidades do mundo como Argentina na cidade de Mar de la Plata (Diaz et al, 2007), na Escócia (Stewart et al, 2002), França (Boulay et al, 1999), Austrália (Barnett et al, 2008), Canadá em Quebeque (Feldman et al, 2004). Estudos sobre a sazonalidade na admissão de pacientes com insuficiência cardíaca identificaram maior ocorrência no inverno.…”