Calculation for Males
Calculation of Risk difference, risk ratio, Odds ratio and crude rates for pancreatitis on diabetes exposure. The data is stratified by sex to remove the confounding effect caused by the sex factor. The data is obtained from a National Health Prevalence Survey aiming at obtaining the incidence rates of pancreatitis based on different identified risk factors(Davison, 2015). In this calculation, we will only focus on diabetes as the only risk factor although there others which were studied and observed in the national prevalence survey. The calculations will be performed based on the sex groups – males and females.
|
Diabetes |
Cases |
Participants |
Total |
|
Yes |
7 |
998 |
1,005 |
|
No |
28 |
2,597 |
2,625 |
|
Total |
35 |
3,595 |
3,630 |
Incidence of pancreatitis among exposed males (with diabetes)
Incidence of pancreatitis among the unexposed males (without diabetes)
Females
|
Diabetes |
Cases |
Participants |
Total |
|
Yes |
4 |
488 |
492 |
|
No |
24 |
3,949 |
3,973 |
|
Total |
28 |
4,437 |
4,425 |
Incidence of pancreatitis among exposed females (with diabetes)
Incidence of pancreatitis among the unexposed females (without diabetes)
According to the calculation shown above, females with diabetes had higher incidence risks of pancreatitis within the 12-month period the study was conducted. Contrary to that, males who did not have diabetes had a higher risk that the females who were not exposed to the diabetes condition. Males without diabetes had higher risks of developing Pancreatitis compared to those exposed to diabetes. On the other side, females with diabetes had greater risks of developing the condition compared to those who were not exposed. This shows that sex was a confounding factor within the study because exposure to diabetes had different effects on the development (risk) of pancreatitis(Bland & Altman, 2000; Pandis, 2012).
Due to the confounding effect brought about by the sex of the study participants, the risk difference between exposed and unexposed groups was different among these two exposure groups. There was a negative effect of the exposure to the males, which indicates that having diabetes – the risk of developing pancreatitis reduced by 0.011(Schmidt & Kohlmann, 2008). Contrary to these findings, females who had diabetes had an increased risk of developing pancreatitis. The risk difference between the exposed and non-exposed groups was 0.00209. This difference indicates that exposed women had an increased risk of 0.00209. We can state that based on the evidence, exposure to diabetes has a greater absolute effect on the risk of pancreatitis compared to the women.
Risk ratios is also another way to compare risks within different groups. Men study participants had a risk ratio of 0.6453, which indicates that those who were exposed had a reduced risk of developing pancreatitis by 35.47%(El-Masri, 2013). Contrary, women who were exposed had an increased risk (34.6%) of developing pancreatitis compared to the unexposed. Based on the relative risk statistics, we can conclude that the rate at which the exposure increased the risk to the females is approximately the same as that of the reduced risk to the females. There were no great differences between the odds ratio and the risk ratios – they also have similar explanations on the risk of developing pancreatitis.
Calculation for Females
Crude risk rates are also calculated to compare the risk of developing pancreatitis among males and females and creating an overall statistics for both groups. Based on the crude rate statistics, male participants have a greater risk (by 0.33%) of developing pancreatitis than their female counterparts. The overall risk of developing pancreatitis is 0.00782(Schmidt & Kohlmann, 2008).
A cohort study conducted in Western Sydney to investigate the effect of diabetes on the development of pancreatitis within a period of 12 months.
Males
|
Pancreatitis |
|||
|
Diabetes |
Cases |
Participants |
Total |
|
Yes |
41 |
675 |
716 |
|
No |
9 |
450 |
459 |
|
Total |
50 |
1125 |
1175 |
Incidence of pancreatitis among exposed males (with diabetes)
Incidence of pancreatitis among the unexposed males (without diabetes)
Females
|
Pancreatitis |
|||
|
Diabetes |
Cases |
Participants |
Total |
|
Yes |
94 |
301 |
395 |
|
No |
45 |
450 |
495 |
|
Total |
139 |
751 |
890 |
Incidence of pancreatitis among exposed (with diabetes)
Incidence of pancreatitis among the unexposed (without diabetes)
Incidence of pancreatitis among exposed (with diabetes)
Incidence of pancreatitis among the unexposed (without diabetes)
Assuming there was no loss of follow-up in the study, the risk of developing pancreatitis among the male group was 0.0573 compared to the females’ risk of 0.238. Based on this statistics, females had very high risk compared to the males. The unexposed group of male participants in the study had a lower risk of developing the condition. In the same manner, women with diabetes had a higher risk of pancreatitis compared to those without. We can, therefore, state that being exposed to diabetes increased the risks of developing pancreatitis for both groups.
The absolute of effect of the diabetes exposure was greater among the females (0.147) compared to the male (0.0377) study participants. This shows that sex was a significant confounding factor in the study because the exposure affected the females differently compared to the male participants. Based on the risk difference statistics, exposure to diabetes increased the risk of developing pancreatitis among the females by 14.7%. On the other side, the risk of developing the condition among the males increased by 3.77%.
The male group had a higher relative risk compared to the female participants’ group. Males who had diabetes had 2.923 more times of developing pancreatitis condition that those who were not exposed. On the other side, exposed women in the study had 2.615 more times of having pancreatitis than those who were not having diabetes. Based on the odds ratio statistics, diabetic female participants had 3.123 more times risk of developing pancreatitis than the unexposed. The males’ (3.037) odds ratio was slightly lower than females’. Crude pancreatitis among females is greater than that of the males. The overall risk of developing pancreatitis among the people of Western Sydney is 0.0915.
Discussion
Unexposed males in the cross-sectional study had a higher risk of pancreatitis compared with the exposed group – which was the inverse in the prospective cohort study. Observations between the cross-sectional and prospective studies based on the female group’s incidence risks were the same. Exposed females had higher risks of developing pancreatitis than the unexposed. The difference in obtained risks could have been caused by the difference in study designs, which varies the quality and certainty of the obtained findings(Euser, Zoccali, Jager, & Dekker, 2009; Levin, 2006).
A risk ratio of among the males was 0.64 in the cross-sectional study and 2.923 from the prospective cohort study. This is a very great variation in the statistics between the two studies which can be explained by the difference in the studies. The females’ relative risks are 1.346 and 2.615 for the cross-sectional and prospective cohort respectively(Kamangar, 2012). The relative risk obtained from the prospective cohort is approximately double of the value obtained using the cross-sectional study. In the same manner, the odds ratio statistics vary for both studies, with smaller values obtained for the cross-sectional study and significantly higher values for the prospective cohort. Also, the crude risks for both sex groups are significantly lower for the cross-sectional study compared with those obtained from the prospective study. In general, the prospective study reported a significantly greater risk (0.0915) of developing pancreatitis condition than the cross-sectional study (0.00782). We can conclude that prospective cohort study was more powerful to detect cases of pancreatitis compared to the cross-sectional study(Siri-Tarino, Sun, Hu, & Krauss, 2010).
According to the figure above, it shows that inflammation is one of the conditions that can be caused by diabetes. Due to hyperglycemia, insulin resistance and hyperinsulinemia, a patient can develop hypertension leading to CVD among other conditions such as CHD(Braganza, Lee, McCloy, & McMahon, 2011; Davison, 2015). Some risk factors for diabetes such as smoking, obesity, poor diet and physical inactivity are also displayed in the causal diagram(Noel, Braun, Patterson, & Bloomgren, 2009).
References
Bland, J. M., & Altman, D. G. (2000). The odds ratio. Bmj, 320(7247), 1468.
https://doi.org/10.1136/bmj.320.7247.1468
Braganza, J. M., Lee, S. H., McCloy, R. F., & McMahon, M. J. (2011). Chronic pancreatitis. Lancet, 377(9772), 1184–97.
https://doi.org/10.1016/S0140-6736(10)61852-1
Davison, L. J. (2015). Diabetes mellitus and pancreatitis – cause or effect? Journal of Small Animal Practice.
https://doi.org/10.1111/jsap.12295
El-Masri, M. M. (2013). Odds ratio. The Canadian Nurse, 109(6), 14.
https://doi.org/10.1054/ebog.2000.0196
Euser, A. M., Zoccali, C., Jager, K. J., & Dekker, F. W. (2009). Cohort studies: Prospective versus retrospective. Nephron – Clinical Practice.
https://doi.org/10.1159/000235241
Kamangar, F. (2012). Confounding variables in epidemiologic studies: Basics and beyond. Archives of Iranian Medicine.
https://doi.org/012158/AIM.0014
Levin, K. A. (2006). Study design III: Cross-sectional studies. Evidence-Based Dentistry, 7(1), 24–25.
https://doi.org/10.1038/sj.ebd.6400375
Noel, R. A., Braun, D. K., Patterson, R. E., & Bloomgren, G. L. (2009). Increased risk of acute pancreatitis and biliary disease observed in patients with type 2 diabetes: A retrospective cohort study. Diabetes Care, 32(5), 834–838.
https://doi.org/10.2337/dc08-1755
Pandis, N. (2012). Risk ratio vs odds ratio. American Journal of Orthodontics and Dentofacial Orthopedics.
https://doi.org/10.1016/j.ajodo.2012.08.003
Schmidt, C. O., & Kohlmann, T. (2008). When to use the odds ratio or the relative risk? International Journal of Public Health, 53(3), 165–167.
https://doi.org/10.1007/s00038-008-7068-3
Siri-Tarino, P. W., Sun, Q., Hu, F. B., & Krauss, R. M. (2010). Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. The American Journal of Clinical Nutrition, 91(3), 535–546.
https://doi.org/10.3945/ajcn.2009.27725.
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