Treating subclinical hypothyroidism reduces ischemic heart events
Treatment with levothyroxine reduces events in younger but not in older patients
Tuesday, 24 April 2012
Treating subclinical hypothyroidism appears to reduce event related to ischemic heart disease events in younger patients, according to a report published Online First in Archives of Internal Medicine.
Subclinical hypothyroidism is defined as an elevated serum thyrotropin level in the presence of normal thyroid hormone concentrations. The condition is relatively common and often asymptomatic, although recent meta-analyses have suggested it can increase the risk of cardiovascular events and death, especially in young to middle-aged adults.
Researchers at Gateshead Health NHS Foundation Trust and Newcastle University used the UK General Practitioner Research Database to identify patients with new subclinical hypothyroidism recorded during 2001 with outcomes analysed until March 2009. Subclinical hypothyroidism was identified in 3,093 younger patients (40-70 years) and 1,642 older patients (older than 70 years). Levothyroxine was used to treat 52.8 per cent of younger patients and 49.9 per cent of older patients.
The results showed that in the younger group, the number of such events was 39 per cent lower among patients taking levothyroxine than in untreated patients, a significant difference. All-cause mortality also was lower in the treated younger patients, by 64%.
However, in the older patients, there were no significant differences between treated and untreated patients in the rate of ischemic heart disease events or all-cause mortality.
Dr Salman Razvi of the Institutes of Human Genetics at Newcastle University said: “Our data suggest that physicians can be reassured that levothyroxine treatment of subclinical hypothyroidism in patients aged 40-70 years is not harmful and may be associated with modestly improved medium-term health outcomes.”
He added that the findings "may provide the best evidence about the management of subclinical hypotension for some time," given that no prospective randomized controlled trials of the issue have yet begun. “Only adequately powered randomized controlled intervention trials will be able to demonstrate whether treatment of subclinical hypothyroidism is worthwhile in terms of improvement in both cardiovascular disease risk and symptoms," he said.