Seasonal effects on suicide rates

Myth: Seasonal Variations of Suicide are Higher in Winter

A common belief is that suicide rates peak during the cold and dark months of the winter season. This overtly publicized notion is actually a myth because various studies, which have been thoroughly bolstered by 'media coverage associating suicide with the holiday season', have shown that the prevalence of suicide occurs most frequently during late spring and early summer months/seasons.

Proclaimed Myth

For many reasons, the myth that suicides have a preemptive tendency to peak during spring and early summer months and, in turn, not during autumn or winter months is highly regarded as counter-intuitive. One claim is that individuals who reside within healthy/suitable living environments generally enjoy the sunlight that spring and summer seasons have to offer moreover than autumn or winter months. Others suggest that the difficulty of enduring harsh meteorological climates, contracting viral diseases such as pneumonia and hypothermia, and the minimal amount of sunlight could lead to emotional states of helplessness and gradually ensue in suicidal behaviors. Whether the contributing factors may be demographic, environmental, financial, political, psychopathological, or even socioeconomic, "seasonal variations and meteorological characteristics" are considered to be significant in determining the prevalence of suicide within most populations.

From what the general underlying conception holds, depressive moods-during cold and dark winter months-have a correlation with suicidal attempts, idealizations, and plans. This, however, has been deemed false due to "present findings suggest that the seasonal distribution of suicides indeed is a counterintuitive fact for everyday reasoning. Seasonal differences in the risk of suicide may also matter for the proper assessment of suicidality and the treatment of suicidal individuals."

Supporting the Myth

Since suicide is the tenth leading cause of death among the entire population , it has long been believed that there is a definite correlation between volatile rates of depression and winter seasons, mainly because of the Seasonal Affective Disorder.

Seasonal Affective Disorder

The Diagnostic and Statistical Manual of Mental Disorders, 4th ed., (DSM-IV) categorizes seasonal affective disorder as a specifier of major depression.

According to Webmd, SAD is certain type of depression that typically affects individuals on a negative spectrum (primarily) due to the lack of sunlight, in which the person is exposed to throughout a normally cold seasonal time frame. Other factors that give light to this disorder include: impaired sleep-wake schedule, disrupted circadian rhythms, and the decrease in a neurotransmitter called serotonin. Keep in mind that if a parental or related guardian has suffered from SAD, there is a high likelihood of the offspring/blood-related individual will be susceptible to it as well. Symptoms include loss in energy, decrease in overall appetite, social withdrawal, and unhappiness/irritability. In severe enough cases, these symptoms can even lead to suicidal attempts, ideations, and/or plans. Even though the convergent lines of clinical research do not necessarily prove that depression and winter have an exact correlation, the collaboration of these symptoms could be indicative of suicidal cognitions.

On the other hand, Pendse, Westrin, and Engstrom’s experimental research study on temperament traits in the seasonal affective disorder and suicidal attempters determined that their clinical experience shows “the suicidal behavior of SAD patients is not a prominent problem, even though SAD patients often present suicidal ideation.” Pendse and colleagues compared a small sample of patients (population sample of eighty-seven) who suffer from seasonal affective disorder to hospitalized suicide attempters (population sample of sixty-five) who had undergone “non-seasonal major depression” by using the Comprehensive Psychopathological Rating Scale (CPRS). . Their results state that the SAD controlled group had a significant probability (p-value of < .05) of scoring higher on non-psychotic tests than the non-SAD suicidal attempters—when both experimental control groups being analyzed for items such as “hostile feelings, indecision (negatively), lassitude, failing memory, increased sleep, muscular tension, loss of sensation or movement, and disrupted thoughts, and the observed items were perplexity, slowness of movement (negatively), and agitation.” . These particular results are able to scientifically contradict the widely held intuition that suicides and seasonal affective disorder hold essentially no correlation with each other.

Refuting The Myth

A generalized reason, in which people grasp as believable, behind the claim that suicide rates are elevated during the holidays is that “holiday cheer amplifies loneliness and hopelessness in people who have lost loved ones, or who have high expectations of renewed happiness during the holiday season, only to be disappointed.” .

As stated by Russell G. Foster and Leon Kreitzman in their book "Seasons of Life", the seasonality of death is primarily being influenced by one’s living standards. Meteorological fluctuations have amounted in a steady decline in mortality rates from diseases “that had previously been most severe in the summer months, such as dysentery, gastroenteritis, tuberculosis, and other infectious and parasitic diseases…resulting from poor socioeconomic progress resulting from increased prosperity and social welfare.”

Another inaccurate, but yet accepted, proclivity to suicides increasing in the winter season is that people think the overwhelming emotional state of anxiety comes from inevitable amounts of stress, over-exhaustion, and irritation that comes hand-in-hand when preparing for the holidays. For instance, interpersonal problems such as: suicides of a family member within the past five years, intimate partner problems, and being a victim of perpetrated/interpersonal violence can amount in re-consolidating traumatic memories and, therefore, cause withstanding neurotic feelings. Additionally, life stressors that determinedly impact ones life on a negative spectrum can include: recent crises, physical health problems, and job/work life difficulties in sustaining fiscal goals. Statistics on these suicidal trends can be found within the CDC website. .

United States National Research Studies

Even though the media’s primary focus, insofar, on suicides during the winter season, the Center for Disease Control and Prevention and the National Center for Health Statistics report that suicide rates in the United States are, to contrary belief, the lowest during the winter months and highest in the summer and springtime. In consonance with F. Stephen Bridges’s article “Seasonal Changes in Suicide in the United States, 1971 to 2000”, his findings assert that "A high incidence in early spring (April and May) and…also a low incidence in winter". Bridges's unique methodology was examined in three specific ways: analyzing the monthly distribution of suicides within a time from of the 1970s, 80s, and 90s; secondly, a chi-square test was provided to demonstrate the exact evenness of the monthly averages; and finally a "harmonic time series model" was applied with six observable harmonic cycles within given year. Conforming to the study's results, the 1970's distributed a large incidence (p<.01) in its bimodal paradigm.

Additionally, evidential data shows that "about 47% of the total variances can be explained by the seasonal components" within that given decade. In regards to the next decade (1980-1990), "The seasonal component of suicide incidence for the time period 1981 through 1990 is clearly significant and records about a 27.7% increase in seasonal contribution by comparison with the previous period". As for the concluding decade in the study (1990-2000), results signify comparable data because of the "the significant seasonal rhythm were explained in 63% of the total variation." .

Another study by French sociologist Émile Durkheim presents similar research results in refuting the myth that suicides occur more frequently during winter seasons/months. Insofar of his conclusive experimental findings, Durkheim reported that most suicides occurred in the spring, but not summer. In cultivating an explanation for this particular scrutiny, Durkheim sided with his sociological cognizance and digressed from the role of nature. From what Durkheim professes, most suicides took place in spring because "everything begins to awake; activity is resumed, relations spring up, interchanges increase. In other words, it is the density of human interactions, and not the environment that caused higher incidence of suicide in spring or summer." .

Furthermore, researchers who found a linked association between seasonality and suicide ascertained comparable results in that suicides do actually have a peak during the spring or summer. . ,.

International Research Studies

According to F. Stephen Bridges (a researcher on homicide victims and victims of homicide-suicide), recent research from industrialized countries such as: Finland, Sweden, Australia and New Zealand, and England and Wales has provided a relevant amount of information in light of a noticed pattern in the decrease of suicide seasonality over the past few decades.

Within the country of Greece, research studies indicate that the seasonal variations of suicide mortality are “more frequent during the spring and summer months…but no regular annual rhythm”. Interestingly enough, a handful of researchers that conducted these meteorological studies stated that "the seasonal variation of suicide follows more closely the seasonal variation of sunshine rather than the corresponding variation of temperature".

As for the tropical country of Brazil in the Southern Hemisphere, studies have deduced that "the peak number of suicides occurred in spring (November) in men and women of Rio Grande do Sul state and in men of Parana and Santa Catarina states, and in early summer (January) for women of Parana´ state." When analyzing photoperiod, there have been very few scientific assessment studies that have focused on seasonal suicide variations within the southern hemisphere because most data has been of what is known about the seasonal variation in suicide rate originates from studies have been ordained in the northern hemisphere.

In conjunction with oversees research studies, a former member in the field of Preventive Medicine, Eleni Petridou, conducted a collaborative international study that involved twenty different countries. The documented outcome was an early summer peak in suicides. Upon hers and her research colleagues’ conclusion, “seasonal variation in suicide incidence could be explained by the increase in sunshine in summer months because of a relationship between sunshine, high temperatures and suicide rate.” </ref>,.

In opposition to the corresponding results previously stated, Australian researchers, J. Edwards and F. Whitlock, that studied the seasonal variations in accordance with suicidal rates found a “spring peak in the number of suicides committed in Brisbane, Australia, but the results were not statistically significant…and also that Dublin reported that the incidence of suicide varied according to seasons in the northern hemisphere, but contrary results were found for the southern hemisphere.” .

Risk Factors and Hypothesized Causes

Biological

Biological explanations tend to focus on seasonal variation in hormone changes and neurotransmitter levels.

Conclusion

As may strong scientific findings have indicated, indubitable fluctuations in suicide rates are evidently associated with seasonal variations and changes throughout a given meteorological pattern. Due to an excessive amount of in-depth scientific experiments and studies, the consensus on effectiveness of the seasonal myth of suicides in the winter indicates that suicide rates are indeed higher during springtime and/or summer and are lower during the winter season and its neighboring months.

Albeit the varying proclamations and tendencies regarding the myth about suicides during the winter being true, numerous amounts of studies and data have emerged within the past several decades to clearly elucidate any ambiguity in that the myth is factual. Specific evidence concludes that suicide numbers are apt to occur more in the summer as opposed to winter, in contrast to the general theorized notion.

Body of Article

The BDI has demonstrated validity in both psychiatric and normal samples.