Suicide in Newfoundland and Labrador: A Linkage Study Using Medical Examiner and Vital Statistics Data

Article excerpt

Objective: To examine suicide epidemiology in Newfoundland and Labrador from 1997 to 2001.

Method: Data from the Office of the Chief Medical Examiner (CME) were linked with data derived from the Canadian Vital Statistics Death Database. Ninety-five percent confidence intervals (CI) were calculated to assess variation of rates. We used the chi-square test to compare categorical data.

Results: The CME recorded 225 suicide deaths, compared with 187 in the Canadian Vital Statistics Death Database. Most deaths not coded as suicide in the national database were coded as accidental. Using the CME data, the overall suicide rate was 9.5/100 000, aged 10 years and older. The rate among males (15.8/100 000, 95%CI, 10.7 to 20.8) was almost 5 times that of females (3.3/100 000; 95%CI, 1.0 to 5.5). Age-standardized rates decreased over the study period, from 10.9 to 8.0/100 000; however, the difference was not significant. The proportionate mortality ratio for suicide deaths was highest among those aged 10 to 19 years (20.0%) and decreased with age. The suicide rate was highest among those aged 50 to 59 years. The rate for unpartnered individuals (17.0/100 000, 95%CI, 10.7 to 23.0) was significantly higher, compared with partnered individuals (5.1/100 000; 95%CI, 2.5 to 7.8). Males used more violent methods than females. Suicide was significantly higher in Labrador (27.7/100 000, 95%CI, 18.4 to 37.0), an area with a higher Aboriginal population, compared with the island of Newfoundland (8.5/100 000, 95%CI, 7.3 to 9.7). Psychiatric illness was the most common predisposing factor.

Conclusions: Suicide deaths are highest among males, unpartnered individuals, and individuals with psychiatric disorders.

Can J Psychiatry 2008;53(4):252-259

Clinical Implications

* Psychiatric illness is a common, predisposing factor for suicide.

* Males and individuals who are unpartnered are at a higher risk of suicide than their partnered counterparts.

* Evidence suggests that suicide is underreported in national statistics in Canada.

Limitations

* Not all psychiatric conditions were confirmed using DSM-IV criteria; however, CME records indicated medical care for psychiatric illness.

* Estimates of predisposing factors may be underestimated owing to the limited information available for some individuals.

* Partnered status might not be accurately reflected because any individual living common law would have been classified as single or unpartnered.

Key Words: suicide, epidemiology, Newfoundland and Labrador

Abbreviations used in this article

BD bipolar disorder

CI confidence interval

CME Chief Medical Examiner

ICD International Statistical Classification of Diseases

PMR proportionate mortality ratios

SD standard deviation

Suicide is a significant, but largely preventable, public health concern. In 2000, about 1 million people worldwide died from suicide, representing a global mortality rate of 14.5/100 000, or 1 death every 40 seconds.1 Worldwide, suicide rates have increased by 60% in the last 45 years.2 Although it is well known that suicide is highest among males and rates tend to increase with age, rates among young individuals have been increasing at a greater pace than in the elderly, a phenomenon that has been referred to as the ungreying of suicide.3

The most recent data available for Canada indicates that suicide claimed more than 3700 lives in 2003.4 The overall age-standardized suicide rate in Canada for 2003 was 11.3/100 000: 17.8/100 000 males and 5.1/100 000 females.4 Trend data indicate an overall decline in the suicide rate in Canada from 1979 and 1998.5

The accuracy of official statistics has been the subject of debate for decades and it is generally recognized that suicide tends to be underreported in all jurisdictions.6 It has been suggested that underreporting is attributable to numerous factors, including aspects of the death certification process; knowledge, attitudes, or practices of individuals responsible for certification; cultural, religious, and legal considerations; limitations in the system for gathering and compiling suicide data; and the ambiguous nature of some suicidal acts. …