Incidence of major depressive episode correlates with elevation of substate region of residence

Abstract

Background Major depressive disorder (MDD) is a common disorder that is often associated with suicide. We have recently suggested that elevation may play a role in regional variations in rates of suicide. We hypothesize that there is also a significant correlation between incidence of MDD and elevation of residence. Methods The substate estimates from the 2004 to 2006 National Surveys on Drug Use and Health (NSDUH) report from SAMHSA was used to extract substate level data related to percentages of people 18 years or older who experienced serious psychological distress or a major depressive episode in the past year. Mean elevation of each substate region was calculated by averaging the weighted elevations of its relevant counties. Average elevation for United States counties was calculated using the Shuttle Radar Topography Mission (SRTM) elevation dataset. Pearson correlation coefficients were computed to investigate the association between average substate elevation and rate of serious psychological distress or major depressive episode. Results There was a significant correlation between percentage of people experiencing serious psychological distress in the past year in a substate region and that substate region's mean elevation (r = 0.18; p = 0.0005), as well as between the percentage of people having at least one major depressive episode in the past year in a substate region and that substate region's mean elevation (r = 0.27; p < 0.0001). Conclusions Elevation appears to be a significant risk factor for MDD. Further studies are indicated to determine whether the increased incidence of depression with increased elevation may be due to the hypoxic effects on subjects with MDD.

Cocaine Use in the Past Year Is Associated With Altitude of Residence

“…This finding has been independently replicated, using mortality data covering two decades (1979-1998) and 2,584 U.S. counties (Betz, Valley et al 2011; Brenner, Cheng et al 2011). We additionally found an association between altitude and depression (DelMastro, Hellem et al 2011). Comorbid depression and cocaine use disorder is a risk factor for relapse (Poling, Kosten et al 2007; Stulz, Thase et al 2011).…”

Hypobaric Hypoxia Induces Depression-like Behavior in Female Sprague-Dawley Rats, but not in Males

“…Chronic hypoxia in patients with respiratory or cardiac dysfunction could similarly precipitate depression (Katz, 1982). Residents at altitude are also prone to loss of appetite, disrupted sleep cycles (Maa, 2010) and increased depression (DelMastro et al, 2011;Gamboa, 2011), implying that low brain serotonin levels may be an issue here. Low brain serotonin is also linked to suicidal ideation and attempts ( Joiner et al, 2005).…”

“…A recent study showed that people living at altitude have higher levels of depression than those at sea level (Gamboa, 2011). Extraction of altitude-based data from U.S. national mental health surveys confirm that rates of MDD escalate significantly with elevation of residence (DelMastro et al, 2011).…”

Association Between Altitude and Regional Variation of ADHD in Youth

“…Cocaine and other drug use, such as methamphetamines, have been shown to have an association with depression and mania in bipolar disorder and suicide. Recent studies suggest that the effects of hypoxia may cause an increase of DA that may contribute to these effects (DelMastro et al, 2011; Fiedler et al, 2012; Kim et al, 2011). …”