The effect of ambient temperature on type-2-diabetes: case-crossover analysis of 4+ million GP consultations across England

Abstract

BackgroundGiven the double jeopardy of global increases in rates of obesity and climate change, it is increasingly important to recognise the dangers posed to diabetic patients during periods of extreme weather. We aimed to characterise the associations between ambient temperature and general medical practitioner consultations made by a cohort of type-2 diabetic patients. Evidence on the effects of temperature variation in the primary care setting is currently limited.MethodsCase-crossover analysis of 4,474,943 consultations in England during 2012–2014, linked to localised temperature at place of residence for each patient. Conditional logistic regression was used to assess associations between each temperature-related consultation and control days matched on day-of-week.ResultsThere was an increased odds of seeking medical consultation associated with high temperatures: Odds ratio (OR) = 1.097 (95% confidence interval = 1.041, 1.156) per 1 °C increase above 22 °C. Odds during low temperatures below 0 °C were also significantly raised: OR = 1.024 (1.019, 1.030). Heat-related consultations were particularly high among diabetics with cardiovascular comorbidities: OR = 1.171 (1.031, 1.331), but there was no heightened risk with renal failure or neuropathy comorbidities. Surprisingly, lower odds of heat-related consultation were associated with the use of diuretics, anticholinergics, antipsychotics or antidepressants compared to non-use, especially among those with cardiovascular comorbidities, although differences were not statistically significant.ConclusionsType-2 diabetic patients are at increased odds of medical consultation during days of temperature extremes, especially during hot weather. The common assumption that certain medication use heightens the risk of heat illness was not borne-out by our study on diabetics in a primary care setting and such advice may need to be reconsidered in heat protection plans.Electronic supplementary materialThe online version of this article (doi:10.1186/s12940-017-0284-7) contains supplementary material, which is available to authorized users.

Short-term association between ambient temperature and acute myocardial infarction hospitalizations for diabetes mellitus patients: A time series study

“…Studies from the United States [ 2 – 4 ] and Sydney, Australia [ 5 ] found positive associations between temperature and DM-related complications and mortality, while studies from the Philippines [ 6 ] and China [ 7 , 8 ] found increased DM mortality at both high and low temperatures. Climate change, which is leading to higher average global temperatures [ 10 ], and the rising prevalence of DM have been suggested to pose a “dual threat” in increasing the disease burden [ 11 ].…”

Acute flares of knee osteoarthritis in primary care: a feasibility and pilot case-crossover study

“…Case-crossover studies [ 18 ] have been used to good effect to identify triggers of other acute health events (e.g. [ 19 – 21 ]), and researchers have begun adopting this design to investigate episodic flare-ups of OA [ 22 ]. However, there are a number of challenges and uncertainties, including the ability to identify and recruit individuals at risk of flare-ups to online data collection, efficient and timely capture of these relatively short-lived and currently ill-defined events, and the ascertainment of relevant, transient exposures.…”

Heat-health vulnerability in temperate climates: lessons and response options from Ireland

“…Type-2 diabetic and obese individuals are also at risk of ill-health during high ambient temperatures. In a temperate region (Köppen system classification: temperate, Cfb) English type-2 diabetic patients were found to be at an increased odds of presenting to their medical practitioner on days of high ambient temperature and these odds were elevated for diabetic patients with cardiovascular comorbidities [54].…”