Climatological variations in daily hospital admissions for acute coronary syndromes

Panagiotakos, Demosthenes B.; Chrysοhoou, Christina; Pitsavos, Christos; Nastos, Panagiotis T.; Anadiotis, Aggelos; Tentolouris, Constantinos; Stefanadis, Christodoulos; Toutouzas, Pavlos; Παλιατσός, Α. Γ.

doi:10.1016/j.ijcard.2003.04.050

Cited by 132 publications

(110 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Conceivably, greater visceral vasoconstriction during cold exposure, concomitant with greater increases in sympathetic outflow, may further contribute to augmented pressor responses in older adults and warrants further investigation. The age-related alterations in the acute responses to cold stress observed in the present study may underlie increased cardiovascular risk in older adults exposed to cold environments (5,38,44,50,63). Because isometric exercise is accompanied by robust increases in MSNA and BP (34,37), and coupled with the noted impairments in the sympathetic and pressor responses to cooling, we reasoned that physical exertion in the cold may impart greater challenges to sympathetic control of the cardiovascular system compared with cold exposure alone.…”

Section: Discussionmentioning

confidence: 85%

“…blood pressure; aging; handgrip; whole body cooling AGING IS A PRIMARY RISK FACTOR for cardiovascular disease, the leading cause of death in the United States (18). Furthermore, cardiovascular-related morbidity and mortality increase at low ambient temperatures, especially in older adults (5,38,44,50,63). The acute systemic physiological responses to cold exposure include peripheral and visceral vasoconstriction, elevated plasma norepinephrine, and increased blood pressure (BP) (9,52,62).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Muscle sympathetic nerve activity during cold stress and isometric exercise in healthy older adults

Greaney

Stanhewicz

Kenney

et al. 2014

Journal of Applied Physiology

View full text Add to dashboard Cite

Greaney JL, Stanhewicz AE, Kenney WL, Alexander LM. Muscle sympathetic nerve activity during cold stress and isometric exercise in healthy older adults. J Appl Physiol 117: 648 -657, 2014. First published August 7, 2014 doi:10.1152/japplphysiol.00516.2014.-Cardiovascular mortality increases in cold weather in older adults, and physical activity may impart even greater cardiovascular risk than cold exposure alone. Human aging is associated with exaggerated pressor responses to whole body cooling; however, the sympathetic response to cold stress alone and in combination with isometric exercise is unknown. We hypothesized that cold stress would 1) increase muscle sympathetic nerve activity (MSNA) and 2) augment the MSNA response to isometric handgrip in older adults. Whole body cooling (water-perfused suit) was conducted in 11 young (23 Ϯ 1 yr) and 12 healthy older adults (60 Ϯ 2 yr). Blood pressure (BP; Finometer) and MSNA (microneurography) were measured throughout cooling and during isometric handgrip at 30% maximal voluntary contraction performed at a mean skin temperature (T sk) of 34 and 30.5°C. MSNA was greater in older adults at T sk ϭ 34.0°C and throughout cooling (P Ͻ 0.05). MSNA increased during cooling in older, but not young, adults (young: ⌬0 Ϯ 1 vs. older: ⌬8 Ϯ 1 bursts/min; P Ͻ 0.05). The cooling-induced increase in BP was greater in older adults (P Ͻ 0.05). During handgrip, the increases in MSNA and BP were not different between conditions in either young (⌬14 Ϯ 2 T sk 34°C vs. ⌬12 Ϯ 3 Tsk 30.5°C bursts/min; ⌬20 Ϯ 3 Tsk 34°C vs. ⌬19 Ϯ 3 Tsk 30.5°C mmHg; both P Ͼ 0.05) or older adults (⌬12 Ϯ 1 Tsk 34°C vs. ⌬8 Ϯ 1 Tsk 30.5°C bursts/min; ⌬18 Ϯ 3 Tsk 34°C vs. ⌬17 Ϯ 2 Tsk 30.5°C mmHg; both P Ͼ 0.05). In summary, MSNA increased during cold stress in older, but not young, adults. Furthermore, concomitant cold stress did not alter the sympathetic responses to isometric exercise in either age group, suggesting preserved sympathetic responsiveness during exercise in the cold in healthy aging. blood pressure; aging; handgrip; whole body cooling AGING IS A PRIMARY RISK FACTOR for cardiovascular disease, the leading cause of death in the United States (18). Furthermore, cardiovascular-related morbidity and mortality increase at low ambient temperatures, especially in older adults (5,38,44,50,63). The acute systemic physiological responses to cold exposure include peripheral and visceral vasoconstriction, elevated plasma norepinephrine, and increased blood pressure (BP) (9,52,62). Therefore, alterations in the acute responses to cold may contribute to the clinical relation between cold temperatures and increased cardiovascular-related mortality in primary aging. Perturbations that further challenge systemic physiological function during cold exposure, such as static or dynamic exercise, may result in increased sympathetic activation and excessive increases in BP, imparting even greater risk for an acute cardiovascular event in older adults. As such, understanding age-related changes in the acute sympathetic and...

show abstract

Section: Discussionmentioning

confidence: 85%

mentioning

confidence: 99%

Muscle sympathetic nerve activity during cold stress and isometric exercise in healthy older adults

Greaney

Stanhewicz

Kenney

et al. 2014

Journal of Applied Physiology

View full text Add to dashboard Cite

show abstract

“…Various plausible explanations for this apparent pattern have been proposed, including the effects of colder weather, influenza, air pollution, and photoperiod on cardiovascular disease. In particular, independent investigations from different climates have observed increases in cardiovascular events associated with declines in ambient temperatures (Bull & Morton, 1978;Kunst et al, 1993, Danet et al, 1999Panagiotakos et al, 2004;Cagle & Hubbard, 2005).…”

Section: Introductionmentioning

confidence: 99%

Seasonality and Coronary Heart Disease Deaths in United States Firefighters

Mbanu

Wellenius

Mittleman

et al. 2007

Chronobiology International

View full text Add to dashboard Cite

United States firefighters have a high on-duty fatality rate and coronary heart disease is the leading cause. Seasonality affects the incidence of cardiovascular events in the general population, but its effects on firefighters are unknown. We statistically examined the seasonal and annual variation of all on-duty coronary heart disease deaths among US firefighters between 1994 and 2004 using the chi-square distribution and Poisson regression model of the monthly fatality counts. We also examined the effect of ambient temperature (apparent as well as wind chill temperature) on coronary heart disease fatalities during the study span using a time-stratified, case-crossover study design. When grouped by season, we observed the distribution of the 449 coronary heart disease fatalities to show a relative peak in winter (32%) and relative nadir in spring (21%). This pattern was significantly different (p=0.005) from the expected distribution under the null hypothesis where season has no effect. The pattern persisted in additional analyses, stratifying the deaths by the type of duty in which the firefighters were engaged at the time of their deaths. In the Poisson regression model of the monthly fatality counts, the overall goodness-of-fit between the actual and predicted case counts was excellent ( = 16.63; p = 0.002). Two distinct peaks were detected, one in January-February and the other in August-September. Overall, temperature was not associated with increased risk of on-duty death. After allowing for different effects of temperature in mild/hot versus cold periods, a 1°C increase was not protective in cold weather, nor did it increase the risk of death in warmer weather. The findings of this study reveal statistical evidence for excess coronary heart disease deaths among firefighters during winter; however, the temporal pattern coronary heart disease deaths was not linked to temperature variation. We also found the seasonal pattern to be independent of duty-related risks.

show abstract

“…Collectively, these data indicate that cooling increases left ventricular preload, without affecting left ventricular contractility in older but not young adults. Greater increases in preload and afterload during cooling in older adults contribute to greater increases in indices of myocardial oxygen demand and may help explain the increased risk of cardiovascular events in cold weather.tissue Doppler imaging; echocardiography; age CARDIOVASCULAR-RELATED MORTALITY increases in the cold winter months, particularly in older adults (10,12,23,24,28,40). Associations between increased cardiovascular-related mortality and cold temperatures may be mediated, in part, by acute physiological responses to cold, which include peripheral and visceral vasoconstriction, elevated plasma norepinephrine, and diuresis (33, 38).…”

mentioning

confidence: 99%

Effect of aging on cardiac function during cold stress in humans

Wilson

Gao

Hess

et al. 2010

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

determine whether skin surface cooling increases left ventricular preload and contractility to a greater extent in older compared with young adults we studied 11 young (28 Ϯ 2 yr; means Ϯ SE) and 11 older (64 Ϯ 3 yr) adults during normothermia (35°C water perfused through a tube-lined suit) and cooling (15°C water perfused for 20 min) using standard and tissue Doppler echocardiography. Cooling significantly decreased skin surface temperature in young (⌬2.8 Ϯ 0.3°C) and older (⌬3.0 Ϯ 0.3°C) adults and increased rate-pressure product, an index of myocardial oxygen demand, in older (6,932 Ϯ 445 to 7,622 Ϯ 499 mmHg · beats/ min for normothermia and cooling, respectively), but not young (7,085 Ϯ 438 to 7,297 Ϯ 438 mmHg · beats/min) adults. Increases in blood pressure (systolic and mean blood pressure) during cooling were greater (P Ͻ 0.05) in older than in young adults. Cooling increased preload in older (left ventricular end-diastolic volume from 106 Ϯ 7 to 126 Ϯ 9 ml and left ventricular internal diameter in diastole from 4.69 Ϯ 0.12 to 4.95 Ϯ 0.14 cm; both P Ͻ 0.01), but not young adults (left ventricular end-diastolic volume from 107 Ϯ 7 to 111 Ϯ 7 ml and left ventricular internal diameter in diastole from 4.70 Ϯ 0.10 to 4.78 Ϯ 0.10 cm). Indices of left ventricular contractility (ejection fraction, myocardial acceleration during isovolumic contraction, and peak systolic mitral annulus velocity) were unchanged during cooling in both young and older adults. Collectively, these data indicate that cooling increases left ventricular preload, without affecting left ventricular contractility in older but not young adults. Greater increases in preload and afterload during cooling in older adults contribute to greater increases in indices of myocardial oxygen demand and may help explain the increased risk of cardiovascular events in cold weather.tissue Doppler imaging; echocardiography; age CARDIOVASCULAR-RELATED MORTALITY increases in the cold winter months, particularly in older adults (10,12,23,24,28,40). Associations between increased cardiovascular-related mortality and cold temperatures may be mediated, in part, by acute physiological responses to cold, which include peripheral and visceral vasoconstriction, elevated plasma norepinephrine, and diuresis (33, 38). Recently, we reported an augmented increase in arterial blood pressure during acute cold exposure (nonpainful and noninternal temperature lowering) in older adults (15). This augmented pressor response to cold stress in older adults was strongly associated with increased levels of central arterial stiffness before cooling and an increase in rate-pressure product during cooling (15). This effect appears to be confined to older adults as neither rate-pressure product nor cardiac minute work increase during similar cold exposure in young adults (36,38).Myocardial oxygen demand is affected by a number of factors (17) that may be altered by acute (i.e., cold stress) and chronic processes (i.e., aging). For instance, cold stress that does not induce shivering or d...

show abstract

Climatological variations in daily hospital admissions for acute coronary syndromes

Cited by 132 publications

References 21 publications

Muscle sympathetic nerve activity during cold stress and isometric exercise in healthy older adults

Muscle sympathetic nerve activity during cold stress and isometric exercise in healthy older adults

Seasonality and Coronary Heart Disease Deaths in United States Firefighters

Effect of aging on cardiac function during cold stress in humans

Contact Info

Product

Resources

About