The association between risk factors and hypertension in perak, malaysia.

INTRODUCTION: Hypertension is a major public health problem in Malaysia. A survey was initiated to examine the association of modifiable and non-modifiable risk factors for hypertension in Perak, Malaysia. METHODS: A total of 2025 respondents aged 30 years and above were recruited using a multi-stage sampling method. Hypertension was defined as self-reported hypertension and/or average of two blood pressure readings at single occasion with SBP ≥ 140mmHg or DBP ≥ 90 mmHg. Body mass index (BMI) was defined using the Asian criteria and International Physical Activity Questionnaire (IPAQ) was used to evaluate physical activity. Body weight, height and blood pressure were obtained using standard procedures. Univariate analyses were conducted to examine the associations between risk factors and hypertension. Multiple logistic regression was used to examine each significant risk factor on hypertension after adjusted for confounders. RESULTS: In total, 1076 (54.9%) respondents were found to be hypertensive. Significant associations (p <0.001) with hypertension were noted for increasing age, low physical activity, obese BMI, no education background and positive family history of hypertension. After adjusting for age, sex, ethnicity, education background, family history, BMI, physical activity, smoking and diet, respondents who were obese and had positive family history had higher odds for hypertension (OR:2.34; 95% CI:1.84-3.17 and 1.96 (1.59-2.42) respectively. A significant increase (p <0.001) in risk for hypertension was noted for age. Those with moderate physical activities were 1.40 (1.04-1.78) times more of having hypertension than those active. Poor diet score and smoking were not significantly associated with increased risk for hypertension. CONCLUSION: In conclusion, modifiable risk factors such as BMI and physical activity are important risk factors to target in reducing the risk for hypertension.

3D full field strain analysis of polymerization shrinkage in a dental composite.

OBJECTIVE: The objective of this research was to study the polymerization shrinkage in a dental composite using 3D digital image correlation (DIC). METHODS: Using 2 coupled cameras, digital images were taken of bar-shaped composite (Premise Universal Composite; Kerr) specimens before light curing and after for 10 min. Three-dimensional DIC was used to assess in-plane and out-of-plane deformations associated with polymerization shrinkage. RESULTS: The results show the polymerization shrinkage to be highly variable with the peak values occurring 0.6-0.8mm away from the surface. Volumetric shrinkage began to significantly decrease at 3.2mm from the specimen surface and reached a minimum at 4mm within the composite. Approximately 25-30% of the strain registered at 5 min occurred after light-activation. Application of 3D DIC dental applications can be performed without the need for assumptions on the deformation field. SIGNIFICANCE: Understanding the local deformations and strain fields from the initial polymerization shrinkage can lead to a better understanding of the composite material and interaction with surrounding tooth structure, aiding in their further development and clinical prognosis.