Science

Solving the Mood Riddle

According to two studies, Nigeria is the happiest country with the lowest rates of mental illness. Huh?

According to the World Bank, the average Nigerian earns $300 a year and has a life expectancy of 45.3 years. Nearly six percent of the young female population there has HIV, only 7.1 in a thousand has a computer, electricity and other services are luxuries, and the country is drowning in $31.1 billion of debt. Yet, apparently, the Nigerians are onto something. In 2003, a World Values Survey of more then 65 countries ranked Nigeria number one in terms of happiness.

That finding, apparently, was no fluke. In June 2004, a major World Health Organization survey of 14 countries and two Chinese cities found those impoverished but exuberant Nigerians putting the affluent but angst-ridden Americans and Europeans to shame with a 12-month prevalence of mood disorders of 0.8 percent, far less than any of the surveyed nations. The US had the dubious distinction of leading the pack at 9.6, while Shanghai clocked in at 1.7, Beijing 2.5, Japan 3.1 and the European nations ranged from 3.6 for Germany to 9.1 for the Ukraine.

The WHO Survey was led by Ronald Kessler PhD of Harvard, who was the principal investigator of the ground-breaking US National Comorbidity Survey of 1991-1992 and its follow-ups, as well as the director of various other WHO population studies. Nigeria was the only African nation surveyed. The two Latin American nations in the study and Lebanon had far more in common with the European nations than with either Nigeria or the Asian populations. Other survey findings documented Americans out in front by a wide margin in anxiety disorders (at 18.2 percent compared to the second place French at 12 percent) and number two in substance use (3.8 percent compared to 6.4 percent for the Ukrainians).

In all, 26.4 percent of Americans had a mental illness over the past 12 months - 7.7 in the serious category and 9.4 percent moderate - outpacing second place Ukraine by nearly six points. The one-third serious mental illness to total mental illness ratio held steady across all nations. Other European totals ranged from 8.2 percent Italy to 18.4 percent France. Japan finished at 8.8 and Nigeria and Shanghai brought up the rear at 4.7 and 4.3, respectively.

Those with serious disorders reported that they were unable to carry out their usual activities for about 30 days owing to their illness. The predictable exception was Nigeria at 15.2 days. US residents spent 66.9 days under the covers and Italians kept the lights out for 206.4 days.

The survey did not offer any reasons for why Americans and Europeans are so depressingly ill, but it will undoubtedly spur researchers to look for smoking guns. Based on earlier cross-national population data, Joseph Hibbeln MD of the NIH in two studies found that people in countries that consumed a lot of fish (such as Japan) experienced less depression and bipolar disorder. Similarly, Arthur Westover MD of the University of Texas Southwestern Medical Center discovered that sweet tooth populations (such as the US) coincided with higher rates of depression.

An obvious research priority is finding out what makes the Nigerians so extraordinarily resilient in the first place. Call it Factor X, the why things work effect. First we need to determine if the WHO investigators got this part of the study right. Then, should the figures check out, we should send in the troops - geneticists, physicians, epidemiologists, sociologists, psychologists, anthropologists, environmental scientists ... quantum physicists if it’s even remotely relevant.

At the same time, we need to look at the problem from the other end - namely why we have a mental illness epidemic in the west despite access to reasonably effective treatment. Call it Factor Q, the why things fail effect. Granted, so-called access can be a cruel joke. The survey found that only about half of those with serious mental illness in western countries are being treated, and a third and a quarter respectively for moderate and mild illness. Still, shouldn’t we be hearing that the experts have the situation under control?

Solving these riddles shouldn’t be impossible. Between the failings of the successful nations and the apparent success of a failing one lies the dream of every visionary in the field - a new mental health paradigm, the answers to Factors X and Q. Excelsior.

The Community Factor

In my book, "Living Well with Depression and Bipolar Disorder," I reported:

"When I reported the Nigerian mood puzzle on my Website, one of my readers, Anna, had this to say: "What do the Nigerians have that we don't? The answer is COMMUNITY.

"Who's going to tell her that she's wrong? Is sense of community yet another victim of modern life, and is the resulting isolation driving us to hopelessness and despair? Could the antidote be as simple as getting out the door and meeting people?"

Updated Feb 11, 2008

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