[Drugs and heat wave: SIRIUS, a multicentric case-control study in patients older than 65 years during 2007 summer in...

To evaluate in real conditions the role of drugs in heat-related adverse effects.

We performed a multicentric case-control study in 3 university hospitals in France, including 36 cases (patients older than 65 years hospitalized with hyperthermia or dehydration between 1st July and 31st August 2007) and 51 controls. We compared drugs and changes in drug dosage according to the values of renal function.

At inclusion, clearance creatinine was available for only 12 patients (mean = 31.6 ml/min), and three-fold higher in controls (p < 0.001). Cases took more drugs than controls (4.3 vs. 3.9; p < 0.001), particularly neuroleptic drugs (3.6% vs. 0.5%; p = 0.007).

Despite its small size, our study shows that patients suffering from dehydration in summer are those with more severe renal impairment, taking more drugs (particularly neuroleptics). This pilot work could allow to improve methodology of further studies on drugs during heat waves.