Neither shall he multiply wives to himself, that his heart turn not away

Polygamy increases risk of heart disease by more than 4-fold
Risk and severity of heart disease increases with the number of wives

The 687 married men in the study had an average age of 59 years and 56% had diabetes, 57% had hypertension and 45% had a past history of coronary artery disease (CAD). Around two-thirds of the men had one wife (68%) while 19% had 2 wives, 10% had 3 wives and 3% had 4 wives. There were significant baseline differences according to the number of wives. Men with more than 1 wife were more likely to be older, live in a rural area, have a higher income and have a history of coronary artery bypass grafting (CABG).

Dr Daoulah said: “Polygamy may be more frequent in rural areas because it is more culturally acceptable and getting married at a young age is more common. Also, in the regions that we studied, there was a higher percentage of national citizens residing in rural areas compared to urban areas. Men with multiple wives have to be well supported financially, and although Saudis and Emirati people are supported by their governments, polygamists may need more than one income. They may therefore take on extra employment or have the added pressure of travelling daily to urban areas for higher paid work.”

The researchers found a significant association between number of wives and the presence of CAD, left main artery disease (LMD) and multivessel disease (MVD). Risk increased with the number of wives (see figure). After adjusting for baseline differences, the researchers showed that men who practiced polygamy had a 4.6-fold increased risk of CAD, a 3.5-fold increased risk of LMD and a 2.6-fold elevated risk of MVD.
http://www.escardio.org/The-ESC/Press-Office/Press-releases/Last-5-years/Polygamy-increases-risk-of-heart-disease-by-more-than-4-fold

(All right, this is on a tangent)