Other conditions related to risk include age, obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, and prescription drug and alcohol use.

• 其它相关的危险因素还包括年龄、肥胖、发烧、脱水、心脏病、精神病、空气闭塞、日晒，以及服用处方药物和酒精。