Gynaecomastia in onchocerciasis

Many clinical manifestations of onchocerciasis have been described, but we have not seen any reports of gynaecomastia. We are involved in a field study looking at the impact of ivermectin on oncho-dermatitis in hyperendemic communities, and found gynaecomastia in 63 of 301 men examined before being given ivermectin (figure). Many of the men affected were heavily infected with Onchocerca volvulus parasites, and aged between 30–45 years. They also tended to complain of sexual weakness. Other causes of gynaecomastia were looked for and not found. It is now known that the microfilaria of O volvulus, with an absolute number of more than 1000 excess deaths (attributable risk 0·50/1·50 3198=1066). As the table shows, mortality increases during hot periods were larger for women than for men. Age does not appear to be consistently related to excess mortality at high outside temperatures. There also appears to be an interaction between heat and both diagnosis and level of dependence. The highest RRs of dying were observed for psychogeriatric and neurological disorders. Also, there is a tendency for RRs of dying to be higher among patients with a higher level of activities of daily living (ADL) dependence. The RR of dying during periods with high outdoor temperatures (25–29·9°C) is considerably higher for nursing home patients than it is for the population as a whole. In this study we found an RR of 1·50, while on the basis of the results of a previous study we calculated a RR of 1·09 for the whole Dutch population. Although this difference in sensitivity to heat is likely to be at least partly the result of differences in age-distribution, this study shows that within the group of nursing-home patients, age is not consistently related to excess mortality. This suggests that it is the presence of health problems, and not age as such, which determines sensitivity to heat. Like other investigators before us, we found patients with cardiovascular and respiratory conditions to be at risk of dying during hot summer spells, and this is likely to be explained, at least in part, by biological mechanisms such as an effect of water losses on blood viscosity and haemostasis. The highest RRs, however, were observed for psychogeriatric and neurological conditions, and this suggests that inability of patients to adapt to heat behaviourally (taking off clothes, moving to cooler places, drinking enough . . . ) may also be a crucial factor. The high RRs which were observed for patients with many ADL-problems point in the same direction: these will partly reflect underlying pathology, but also are likely to be related to the general helplessness of these patients, and therefore emphasise the dependence of nursing-home patients upon care-takers for effective countermeasures. We conclude that more should be done to prevent nursing-home patients from dying during periods with high outside temperatures, and that introduction of climate control (air conditioning) should seriously be considered.