The effect of altitude and climate on the suicide rates in Turkey

Association of altitude and frailty in Chinese older adults: using a cumulative frailty index model

Objective

The population is aging exponentially and the resulting frailty is becoming increasingly evident. We aimed to explore the association between altitude and frailty, and to identify associated factors for frailty.

Methods

This is a community-based cross-sectional survey. 1,298 participants aged ≥60 years from three different altitudes were included in the study. To quantify frailty, we constructed a frailty index (FI) and a frailty score (FS). The FI was divided into non-frailty, prefrailty, and frailty. The Odds Ratios and confidence intervals (ORs, 95%CIs) were used to evaluate the association between altitude and FI and FS in multivariate ordinal logistic regression and linear regression.

Results

There were 560 (53.1%) participants in the prefrailty and 488 (37.6%) in the frailty group. The FS increased with higher altitude (P for trend <0.001). Multivariate ordinal logistic regression analysis revealed an association between altitude and frailty, OR = 1.91 (95% CI: 1.38-2.64) in mid-high altitude and 2.49 (95% CI:1.40-4.45) in high altitude. The same trend of association was found in the univariate analysis. The FS increased by 1.69 (95% CI: 0.78-2.60) at mid-high altitude and 3.24 (95%CI:1.66-4.81) at high altitude compared to medium altitude.

Conclusion

The study indicates that high altitude exposure is an associated factor for frailty in older adults. This association become stronger with higher altitudes. As a result, it is essential to conduct early frailty screening for residents living at high altitudes.

Suicide and altitude: A systematic review of global literature

OBJECTIVE

The purpose of this systematic review was to synthesize the existing global literature examining the relationship between altitude and suicide.

METHOD

Using the electronic databases PubMed, CINAHL, EMBASE, and PsychInfo published articles in English that addressed the relationship between altitude and suicide as a primary or secondary aim, and included human subjects, where identified. Studies were assessed for quality based on methodological approach and data relevance on a three-point scale (strong, moderate, or weak).

RESULTS

Of the 19 studies related to the purpose and aims, 17 reported evidence of a positive correlation between altitude and increased suicide. Vast design differences were employed within the literature, individual-level suicide data was identified as the preferred level of analysis.

DISCUSSION

The relationship between altitude and suicide is an evolving science with a small but growing body of literature suggesting altitude is associated with an increased risk of suicide. This review identifies the need for additional studies examining both individual-level suicide data and improving geographic precision. Public health nurses have a responsibility to carefully examine the quality of studies and the strength of the evidence when addressing variables associated with suicide.

Suicides in Turkey: 25-year trend (1995-2019)

The assessment of national suicide risks is considered critical in many countries for the establishment of suicide prevention initiatives aimed at considerably lowering suicide rates. The aim of this study is to identify at-risk suicide populations by reviewing the suicides in Turkey over a 25-year period. The Turkish Statistical Institute's suicide statistics for 1995-2019 in Turkey was retrospectively reviewed in current article. The data collected in the study was statistically analyzed using the MINITAB vn 14 software. Between 1995 and 2019, the total number of suicides in Turkey was 66,819, and suicide rates, especially in males, showed an increasing trend in this period. Males comprised 68.3% of the total cases, and most (27.2%) were aged 15-24 years. Suicides mostly occurred between May and July (27.7%), of individuals with a primary school level of education (51.7%) and who were married (6.0 per 100,000). Illness was most important risk factor for suicide (36.8%) and hanging (47.5%) was the leading suicide method in all age groups and in both genders. Despite the fact that Turkey's suicide rate is lower than many other countries, the growth in male suicide rates is concerning. Suicides are likely to become a severe problem in Turkey in the near future unless measures like education, psychiatric evaluations, the reactivation of psychological counseling service phone lines, and the establishment of youth counseling centers, as described in this paper, are taken.

Evaluation of the effects of altitude on biological signatures of inflammation and anxiety- and depressive-like behavioral responses

Over sixteen million people suffer from a depressive episode annually in the United States, with females affected at twice the rate of males. Little is known about the effects of exposure to high altitude on the risk of development of major depressive disorder, despite reports of higher suicide rates at higher altitudes. We hypothesize that exposure to hypobaric hypoxia at high altitude increases endophenotypes of self-directed suicidal violence, including biological signatures of chronic inflammation and vulnerability to anxiety-like and depressive-like behavioral responses in a sex-specific manner. Biological signatures of inflammation, including granulocyte:lymphocyte ratios, monocyte cell counts, and monocyte:lymphocyte ratios were assessed using complete blood count data, anhedonia, and anxiety- and depressive-like behavioral responses were evaluated. We assessed biological signatures of inflammation and behavioral responses in the open-field test, sucrose preference test, and modified Porsolt forced swim test in young adult male and female Long-Evans and Sprague Dawley rats. All tests were conducted near sea level (374 ft [114 m] elevation) and at moderate-high altitude (5430 ft [1655 m] elevation) during acclimation periods of one, two, three, four, and five weeks following shipment from a sea level animal breeding facility (N = 320, n = 8 per group). Exposure to moderate-high altitude induced a biological signature of increased inflammation, as evidenced by main effects of altitude for: 1) increased granulocyte:lymphocyte ratio; 2) increased count and relative abundance of circulating monocytes; and 3) increased monocyte:lymphocyte ratios. Exposure to moderate-high altitude also increased anhedonia as assessed in the sucrose preference test in both male and female rats, when data were collapsed across strain and time. Among male and female Long Evans rats, exposure to moderate-high altitude increased immobility in the forced swim test, without changing anxiety-like behaviors in the open-field test. Finally, granulocyte:lymphocyte ratios were correlated with anhedonia in the sucrose preference test. These data are consistent with the hypothesis that hypobaric hypoxia at moderate-high altitude induces persistent endophenotypes of self-directed suicidal violence including biological signatures of inflammation, anhedonia, and depressive-like behavioral responses.

The Effect of Meteorological, Pollution, and Geographic Exposures on Death by Suicide: A Scoping Review

Suicide is a significant public health concern worldwide and in the United States. Despite the far-reaching impact of suicide, risk factors are still not well understood and efforts to accurately assess risk have fallen short. Current research has highlighted how potentially modifiable environmental exposures (i.e., meteorological, pollution, and geographic exposures) can affect suicide risk. A scoping review was conducted to evaluate the strength of the historical and current literature on the environment’s effect on suicide and suicide risk. Three databases (i.e., Medline, Embase, and PsychInfo) were reviewed to identify relevant studies and two authors independently reviewed studies considering pre-determined inclusion criteria. A total of 46 meteorological studies were included as well as 23 pollution studies and 12 geographic studies. Descriptive statistics, including counts, percentages, review of studies’ sample size (minimum, maximum, median, and interquartile range), were calculated using Excel and SAS 9.4. Overall, strong evidence supports that exposure to sunlight, temperature, air pollution, pesticides, and high altitude increases suicide risk, although effect sizes range from very small to small.

Influence of contextual factors on death by suicide in rural and urban settings

PURPOSE

To examine the association between contextual factors, represented by geographic and community health variables, and suicide among rural and urban Department of Veterans Affairs health care users (VA users).

METHODS

We performed a retrospective cohort study of 12,700,847 VA users between 2003 and 2017. We assigned contextual factors based on individuals' home address at the ZIP Code (area deprivation), county (sunlight exposure, altitude, and community health), and state level (firearm ownership), using publicly available data sources. We grouped contextual factors by quintiles or prespecified thresholds, depending on the nature of each variable. We obtained mortality data from the National Death Index. We measured the effect of living in a place with the highest versus lowest level of each contextual factor on odds of suicide using logistic regression, adjusting for individual compositional factors abstracted from VA electronic medical records data. We used random forest modeling to build prediction models for suicide based on contextual factors among rural and urban veterans.

FINDINGS

Almost all contextual factors we examined were significantly associated with suicide among rural and urban VA users, even after adjusting for individual compositional factors. However, no contextual variables were strong protective or risk factors (0.5<OR>2.0), and prediction models leveraging these contextual factors had poor accuracy among both rural (0.51, 95% CI: 0.48-0.54) and urban (0.53, 95% CI: 0.51-0.55) VA users.

CONCLUSIONS

A wide variety of contextual factors is significantly associated with suicide among rural and urban VA users. However, the factors we measured contributed very little to individual-level suicide risk.

The effect of meteorological variables on suicide

We aimed to reveal the relationship between the meteorological variables and suicide rates (completed suicides and suicide attempts) independently of the seasonal cycle and holiday effects. This is an observational retrospective study. We collected the data on age, gender, and suicide method of all suicide cases transferred to hospitals from the scene by emergency medical services as well as those cases in which the victim died on the scene between January 1, 2017 and June 30, 2019. We also collected data on maximum, minimum, and average temperatures (°C), average humidity (%), and average actual pressure (hPa) measured daily in Ankara. The total number of cases due to suicide between the given dates was 6777. The suicide method in 60.1% of the cases was drug poisoning, which was the most common suicide method. Investigating the effect of meteorological variables on suicide cases (suicide attempts and completed suicides), the present study found that after smoothing the effect of the day of the week and seasonality, an increase in the minimum temperature on the day of the application by 1 unit (1°C degree) leads to an increase in the number of suicides by 0.01 point (0.01 ± 0.005, p = 0.046). There was no significant change in the variables other than the minimum temperature. We believe that the results of the present study will contribute to growing body literature about the epidemiology of suicide. We also believe that there is a need for large-scale studies that include individual data to reveal causality.

Hot Weather and Suicide Deaths among Older Adults in Hong Kong, 1976-2014: A Retrospective Study

Findings of the association between hot weather and suicide in a subtropical city such as Hong Kong are inconsistent. This study aimed to revisit the association by identifying meteorological risk factors for older-adult suicides in Hong Kong using a time-series approach. A retrospective study was conducted on older-adult (aged ≥65) suicide deaths in Hong Kong from 1976 to 2014. Suicides were classified into those involving violent methods and those involving nonviolent methods. Meteorological data, including ambient temperature, were retrieved. Transfer function time-series models were fitted. In total, 7314 older-adult suicide deaths involving violent methods and 630 involving nonviolent methods were recorded. For violent-method suicides, a monthly average daily minimum ambient temperature was determined to best predict the monthly rate, and a daily maximum ambient temperature of 30.3 °C was considered the threshold. For suicide deaths involving nonviolent methods, the number of days in a month for which the daily maximum ambient temperature exceeded 32.7 °C could best predict the monthly rate. Higher ambient temperature was associated with more older-adult suicide deaths, both from violent and nonviolent methods. Weather-focused preventive measures for older-adult suicides are necessary, such as the provision of more public air-conditioned areas where older adults can shelter from extreme hot weather.

Cerebral bioenergetic differences measured by phosphorus-31 magnetic resonance spectroscopy between bipolar disorder and healthy subjects living in two different regions suggesting possible effects of altitude

AIM

Increased oxidative stress in cerebral mitochondria may follow exposure to the systemic hypobaric hypoxia associated with residing at higher altitudes. Because mitochondrial dysfunction is implicated in bipolar disorder (BD) pathophysiology, this may impact the cerebral bioenergetics in BD. In this study, we evaluated the cerebral bioenergetics of BD and healthy control (HC) subjects at two sites, located at sea level and at moderate altitude.

METHODS

Forty-three veterans with BD and 33 HC veterans were recruited in Boston (n = 22) and Salt Lake City (SLC; n = 54). Levels of phosphocreatine, β nucleoside triphosphate (βNTP), inorganic phosphate, and pH over total phosphate (TP) were measured using phosphorus-31 magnetic resonance spectroscopy in the following brain regions: anterior cingulate cortex and posterior occipital cortex, as well as bilateral prefrontal and occipitoparietal (OP) white matter (WM).

RESULTS

A significant main effect of site was found in βNTP/TP (Boston > SLC) and phosphocreatine/TP (Boston < SLC) in most cortical and WM regions, and inorganic phosphate/TP (Boston < SLC) in OP regions. A main effect analysis of BD diagnosis demonstrated a lower pH in posterior occipital cortex and right OP WM and a lower βNTP/TP in right prefrontal WM in BD subjects, compared to HC subjects.

CONCLUSION

The study showed that there were cerebral bioenergetic differences in both BD and HC veteran participants at two different sites, which may be partly explained by altitude difference. Future studies are needed to replicate these results in order to elucidate the dysfunctional mitochondrial changes that occur in response to hypobaric hypoxia.

Association between altitude, prescription opioid misuse, and fatal overdoses

OBJECTIVE

Prescription opioid misuse and fatal overdoses have increased significantly over the last two decades. Living at altitude has been linked to greater reward benefits of other drugs of abuse, and living at altitude may also exacerbate the respiratory depression linked to opioid use. Therefore, we examined the relationships between living at altitude, and prescription opioid misuse and fatal overdoses.

METHOD

State-level past year rates of prescription opioid misuse were retrieved from the Substance Abuse and Mental Health Services Administration. County-level overdose data were extracted from the Centers for Disease Control and Prevention. Multiple linear regression models were fit to determine the relationship between average state elevation and state rates of opioid misuse. Logistic regression models were fit to determine the relationship between county elevation and county-level fatal opioid overdose prevalence.

RESULTS

After controlling for state opioid prescribing rates and other confounders, we identified a significant positive association between mean state altitude and state-level opioid misuse rates for women, but not men. We also found a significant positive association between county-level altitude and prevalence of fatal opioid overdose.

CONCLUSIONS

Living at altitude is thus demographically associated with increasing rates of misuse of prescription opioids, as well as of cocaine and methamphetamine. Animal studies suggest that the hypobaric hypoxia exposure involved with living at altitude may disrupt brain neurochemistry, to increase reward benefits of drugs of abuse. This increased misuse of both stimulants and opioids may increase likelihood of overdose at altitude, with overdoses by opioid use also potentially facilitated by altitude-related hypoxia.