Later colorectal cancer risk linked to high BMI, inflammation in adolescence

Higher-than-normal body mass index and inflammation in late adolescence may be associated with colorectal cancer risk, a cohort study of 239,658 Swedish men showed.

The study’s results suggest that body mass index (BMI) and inflammation in early life may be important to the development of colorectal cancer (CRC), said Dr. Elizabeth D. Kantor and her colleagues.

The study’s participants, who were all between the ages of 16 and 20, were drawn from a cohort of men who underwent a compulsory conscription assessment for the Swedish military between 1969 and 1976 – when only men with severe disability or chronic diseases were exempt from serving in the military.

During the assessments, each young man’s height and weight was measured, which the study’s researchers used to calculate BMIs in kg/m² for the sample. The BMIs were categorized in the following ways: 15 to <18.5 was underweight, 18.5 to <25 was normal, 25 to <27.5 was the lower category of overweight, 27.5 to <30 was the upper category of overweight, and 30 to <55 was obese. Venous blood samples of the entire cohort were also collected during the assessment. These were used to assess inflammation levels as indicated by erythrocyte sedimentation rate (ESR), a nonspecific biomarker of inflammation. The researchers classified each study participant’s ESR as low, moderate, or high. The researchers tracked the incidences of malignant CRC in the cohort for an average of 35 years using the Swedish Cancer Registry.

Men who had been categorized as being in the upper category of overweight at the time of assessment were 2.08 times more likely to get CRC than normal weight men; obese men were 2.38 times more likely to get the disease. Both of these findings were statistically significant. The researchers also determined that a high ESR was associated with a significant 63% increased risk of CRC, using a multivariable adjustment.

“While no other studies have directly addressed the association between early-life inflammation and CRC risk, evidence supports the role of inflammation early in carcinogenesis,” the researchers wrote.

Another novelty of this study is that adolescents’ BMIs were measured instead of being based on recall, as they had been in other researchers’ attempts to determine the relationship between adolescent BMI and CRC risk in adulthood.

“With additional follow-up, and therefore, statistical power, future studies may address how adolescent inflammation and BMI interact to affect cancer risk. Further research is needed to better disentangle BMI and inflammation from associated exposures, and similarly, from exposures at other points in the life coarse,” the researchers wrote.

Read the full study in Gut (doi:10:1136/gutjnl-2014-309007).

[email protected]

Higher-than-normal body mass index and inflammation in late adolescence may be associated with colorectal cancer risk, a cohort study of 239,658 Swedish men showed.

The study’s results suggest that body mass index (BMI) and inflammation in early life may be important to the development of colorectal cancer (CRC), said Dr. Elizabeth D. Kantor and her colleagues.

The study’s participants, who were all between the ages of 16 and 20, were drawn from a cohort of men who underwent a compulsory conscription assessment for the Swedish military between 1969 and 1976 – when only men with severe disability or chronic diseases were exempt from serving in the military.

During the assessments, each young man’s height and weight was measured, which the study’s researchers used to calculate BMIs in kg/m² for the sample. The BMIs were categorized in the following ways: 15 to <18.5 was underweight, 18.5 to <25 was normal, 25 to <27.5 was the lower category of overweight, 27.5 to <30 was the upper category of overweight, and 30 to <55 was obese. Venous blood samples of the entire cohort were also collected during the assessment. These were used to assess inflammation levels as indicated by erythrocyte sedimentation rate (ESR), a nonspecific biomarker of inflammation. The researchers classified each study participant’s ESR as low, moderate, or high. The researchers tracked the incidences of malignant CRC in the cohort for an average of 35 years using the Swedish Cancer Registry.

Men who had been categorized as being in the upper category of overweight at the time of assessment were 2.08 times more likely to get CRC than normal weight men; obese men were 2.38 times more likely to get the disease. Both of these findings were statistically significant. The researchers also determined that a high ESR was associated with a significant 63% increased risk of CRC, using a multivariable adjustment.

“While no other studies have directly addressed the association between early-life inflammation and CRC risk, evidence supports the role of inflammation early in carcinogenesis,” the researchers wrote.

Another novelty of this study is that adolescents’ BMIs were measured instead of being based on recall, as they had been in other researchers’ attempts to determine the relationship between adolescent BMI and CRC risk in adulthood.

“With additional follow-up, and therefore, statistical power, future studies may address how adolescent inflammation and BMI interact to affect cancer risk. Further research is needed to better disentangle BMI and inflammation from associated exposures, and similarly, from exposures at other points in the life coarse,” the researchers wrote.

Read the full study in Gut (doi:10:1136/gutjnl-2014-309007).

[email protected]

Higher-than-normal body mass index and inflammation in late adolescence may be associated with colorectal cancer risk, a cohort study of 239,658 Swedish men showed.

The study’s results suggest that body mass index (BMI) and inflammation in early life may be important to the development of colorectal cancer (CRC), said Dr. Elizabeth D. Kantor and her colleagues.

The study’s participants, who were all between the ages of 16 and 20, were drawn from a cohort of men who underwent a compulsory conscription assessment for the Swedish military between 1969 and 1976 – when only men with severe disability or chronic diseases were exempt from serving in the military.

During the assessments, each young man’s height and weight was measured, which the study’s researchers used to calculate BMIs in kg/m² for the sample. The BMIs were categorized in the following ways: 15 to <18.5 was underweight, 18.5 to <25 was normal, 25 to <27.5 was the lower category of overweight, 27.5 to <30 was the upper category of overweight, and 30 to <55 was obese. Venous blood samples of the entire cohort were also collected during the assessment. These were used to assess inflammation levels as indicated by erythrocyte sedimentation rate (ESR), a nonspecific biomarker of inflammation. The researchers classified each study participant’s ESR as low, moderate, or high. The researchers tracked the incidences of malignant CRC in the cohort for an average of 35 years using the Swedish Cancer Registry.

Men who had been categorized as being in the upper category of overweight at the time of assessment were 2.08 times more likely to get CRC than normal weight men; obese men were 2.38 times more likely to get the disease. Both of these findings were statistically significant. The researchers also determined that a high ESR was associated with a significant 63% increased risk of CRC, using a multivariable adjustment.

“While no other studies have directly addressed the association between early-life inflammation and CRC risk, evidence supports the role of inflammation early in carcinogenesis,” the researchers wrote.

Another novelty of this study is that adolescents’ BMIs were measured instead of being based on recall, as they had been in other researchers’ attempts to determine the relationship between adolescent BMI and CRC risk in adulthood.

“With additional follow-up, and therefore, statistical power, future studies may address how adolescent inflammation and BMI interact to affect cancer risk. Further research is needed to better disentangle BMI and inflammation from associated exposures, and similarly, from exposures at other points in the life coarse,” the researchers wrote.

Read the full study in Gut (doi:10:1136/gutjnl-2014-309007).

[email protected]