This article discusses the comorbidity of asthma and suicide in teenagers. I am linking to it because this is easily explained by Chinese Medicine.  Asthma is a disorder of the lungs and suicide represents the “spirit” of the lung, which is sadness.  This would happen in older folks too, except that they often don’t have the will to make it happen.

http://www.medpagetoday.com/MeetingCoverage/APA/45670?xid=nl_mpt_DHE_2014-05-09&utm_content=&utm_medium=email&utm_campaign=DailyHeadlines&utm_source=WC&eun=g641572d0r&userid=641572&email=collinssparrow@cs.com&mu_id=5774186