Health Reports: Use of cannabis and other illicit drugs

The proportion of Canadians aged 15 or older who admit to using cannabis nearly doubled in 13 years, with the highest rates among teenagers, according to a new study based on data from the Canadian Community Health Survey.

An estimated 3 million people aged 15 or older reported that they used marijuana or hashish at least once in the year before the survey, which was conducted in 2002.

According to the study, published in Health Reports, 6.5% of Canadians reported using cannabis in 1989, 7.4% in 1994, and by 2002, the proportion had reached 12.2%.

Nearly half (47%) of those who had used cannabis in the previous year had done so less than once a month. About 10% reported they had used it on a weekly basis, and another 10% said they used it daily.

The survey also collected data on the use of five other drugs: cocaine or crack, ecstasy, lysergic acid diethylamide (LSD) and other hallucinogens, amphetamines (speed), and heroin.

Overall, 2.4% of people aged 15 or older reported using at least one of these drugs in the past year, up from 1.6% in 1994. An estimated 321,000 people, or 1.3%, had used cocaine or crack, making it the most commonly used of these other drugs.

Men more likely to use cannabis

Men were more likely than women to report having used cannabis in the past year. According to the survey, 15.5% of men reported cannabis use, compared with 9.1% of women. The proportion of men was higher in all age groups except 15 to 17, where there was no difference between the sexes.

Cannabis use was most prevalent among young people, and its use peaked in the late teens. Close to 4 of every 10 teens aged 18 or 19 reported having used marijuana or hashish in the past year. The proportion among 15- to 17-year-olds was about 3 in 10.

Cannabis use drops off after age 24, although numbers in the 25 to 34 and 35 to 44 age groups were still substantial.

Over 10 million tried cannabis at least once

Although most Canadians were not current users of illicit drugs in 2002, many had tried them at some point in their life.

More than 10 million people reported having tried cannabis at least once in their lifetime. These people represented 41.3% of the population aged 15 or older. If one-time users are excluded, the proportion would be 32.0%.

Again, men were more likely than women to have tried cannabis at least once. Lifetime use was highest among young adults aged 18 to 24.

The proportion of residents who had ever used cannabis was above the national average in Nova Scotia, Alberta and British Columbia.

For more information on the article entitled, “ Use of cannabis and other illicit drugs,” which is now available for free online, contact Michael Tjepkema (416-952-4620), Health Statistics Division.

Creutzfeldt-Jakob disease: Only one death related to BSE

This edition of Health Reports also contains articles on deaths from Creutzfeldt-Jacob disease, hospitalization for infection after common surgeries, trends in hospitalization for inflammatory bowel disease, and factors associated with smoking during pregnancy.

Creutzfeldt-Jakob disease (CJD) is a rare, degenerative neurological disease that affects humans. This disease is always fatal.

There are four forms of CJD, only one of which is related to bovine spongiform encephalopathy (BSE), or mad cow disease. Though this form of CJD is extremely rare, the discovery of BSE in a single cow a year ago in Alberta was highly publicized and has had a severe financial impact on Canadian cattlemen.

Only one human death in Canada has been related to BSE.

The overall CJD mortality rate for the 1979 to 2001 period was very low. In fact, there were less deaths from CJD than deaths from extreme cold, or from falls from ladders and scaffolds.

In the 22-year period from 1979 to 2001, 599 deaths were attributed to CJD, an average of 26 a year. The annual number ranged from a low of 14 deaths in 1979 to a high of 44 deaths in 2001. A total of 329 women died of CJD, compared with 270 men.

CJD mortality rates rise sharply with age, especially after 50. Rates were highest at ages 75 to 79 for men, and at ages 70 to 74 for women.

During this two-decade period, the overall CJD mortality rate was lowest in Newfoundland and Labrador and highest in Nova Scotia.

For more information on this article, contact Heather Gilmour (613-951-2114), Health Statistics Division.

Infection after common surgeries

No surgery is free of the risk of infection despite advances in surgical techniques and the use of antibiotics. Some patients do develop infections and have to be re-admitted to hospital, and this becomes costly in terms of hospital resources.

Gall bladder removal, hysterectomy and appendectomy are among the most common surgical procedures performed in Canadian hospitals.

Between 1997/98 and 1999/2000, close to 400,000 patients had one of these surgeries. Taking account of both the initial hospital visit for the surgery, and re-admissions within 30 days, 2.2% of these patients were hospitalized with a post-operative infection.

Re-admissions of patients with infection increased their time in hospital by an average of 5.5 to 8.3 days, depending on the surgery.

The estimated costs associated with these re-admissions ranged between $5.4 million and $6.3 million a year.

For more information on this article, contact Michelle Rotermann (613-951-3166), Health Statistics Division.

Inflammatory bowel disease

Inflammatory bowel disease is a debilitating chronic condition that affects the gastrointestinal tract, frequently developing among people in their 20s and 30s. It refers to two distinct disorders: Crohn's disease and ulcerative colitis.

In 2000/01, a total of 8,320 people were hospitalized with a primary diagnosis of Crohn's disease or ulcerative colitis. However, together these people accounted for 12,248 admissions, indicating that many patients were hospitalized more than once that year.

Crohn's disease and ulcerative colitis made up less than 0.5% of all hospital admissions in 2000/01. However, since the early 1980s, hospitalization rates for the two conditions have been relatively stable. This is in sharp contrast to a steady decline in the overall rate of hospitalization in Canada.

And while the average length of stay for patients with inflammatory bowel disease has declined since the early 1980s, with a consequent decrease in the number of patient-days, this decline did not keep pace with the drop in patient-days overall. So, by 2000/01, the proportion of all days spent in hospital that were attributable to Crohn's disease and ulcerative colitis was actually higher than in 1983/84.

This suggests that managing these conditions is challenging for both the health care system and for the people who are diagnosed with them.

For more information on this article, contact Alice Nabalamba (613-951-7188), Health Statistics Division.

Pregnancy and smoking

The article, entitled "Pregnancy and smoking," examines the proportion of women who reported that they had smoked or had been exposed to smoke when they were pregnant. For more information, contact Wayne J. Millar (613-951-1631), Health Statistics Division.

Complete articles appear in the July 2004 issue of Health Reports, Vol. 15, no. 4 (82-003-XIE, $17/$48; 82-003-XPE, $22/$63), which is now available.

For information about Health Reports, contact Christine Wright (613-951-1765; christine.wright@statcan.gc.ca), Health Statistics Division.