The Study: Hypertension Is Related to Positive Global Sagittal Alignment: A Cross-Sectional Cohort Study                 

 The Facts: 

a. The authors are from the Hamamatsu University School of Medicine, Hamamatsu, Japan with one author being from the Hamamatsu Medical Center, Hamamatsu, Japan.

 b. They wanted to study “the relationship between hypertension and spino-pelvic sagittal alignment…”

 c. They noted that a forward shifted sagittal vertical axis (SVA) is associated with “poor health related quality of life.”

 d. They hypothesized that forward shifted SVA might be involved in hypertension.

 e. The study looked at 655 subject who were evaluated using full spine posteroanterior and lateral radiographs of the subjects.

 f. Subjects were divided into three groups according to their age 50-64, 65-74 and 75 or older.

 g. They found that in the 50-64 age group that both weight and Body Mass Index (BMI) were significantly higher in subjects with hypertension and the SVA was significantly more forward shifted with those who had hypertension, being forward 32.4mm as opposed to the non-hypertensives who were forward shifted 16.0mm.

 h. In the 65-74 aged group weight and BMI were once again significantly higher in those with hypertension as was the SVA which was significantly more forward shifted in the hypertension subjects, being shifted forward 42.7mm as compared to the non-hypertensive group who was forward shifted 30.6mm.

 i. In the 75 or older group the weight and BMI were significantly higher in the hypertension subjects and although the SVA was forward shifted in the hypertension subjects it was not deemed significant being 70.5mm compared to 57.3mm.

 j. The authors offer the following hypothesis: “Regarding the association between hypertension and positive global sagittal alignment, we created the following hypothesis. Hypertension impacts tissue microcirculation, including that in the skeletal muscle. Therefore, the deteriorated microcirculation of the back muscles causes muscle fatigue and muscle degeneration that may result in posture abnormality.”  

  Take Home:

In this study there was a statistically significant difference in the BMI and weight between the hypertensive and non-hypertensive subjects. Also there was a a direct association between forward SVA postures and hypertension in all age groups however, only in the 50-64 and the 65-74 age groups did it reach statistical significance.

 Reviewer's Comments:

I thought it was interesting but I’m not quite sure what we do with this study. I would expect the weight and BMI to be associated with hypertension but it was also very interesting to see the forward SVA be associated in two of the three groups. They also had a very interesting hypothesis that I would like to see tested further.

 Reviewer:  Roger Coleman DC

 Editor’s Comments:  I had a different take here. I was struck by the fact that given an association between two factors (Forward SVA and Hypertension), the authors chose to hypothesize that hypertension was the causal factor of the forward SVA and not the other way around. Admittedly, my own willingness to consider the forward postures as a possible cause of the hypertension is likely a result of my own bias as a chiropractor, but I saw nothing in this study to convince me their hypothesis was any more logical. Also, isn’t it interesting that we now have MDs studying spinal posture and its relationship to a non musculoskeletal health issue using full spine radiography. It’s too bad that studies like this could never, ever, get through a chiropractic institutional review board because of the X-Rays.

Editor: Mark R. Payne DC

 Reference: Arima H, Togawa D, Hasegawa T et al. Hypertension Is Related to Positive Global Sagittal Alignment: A Cross-Sectional Cohort Study. Asian Spine J. 2019 Jul 9. doi: 10.31616/asj.2018.0308. [Epub ahead of print]

 Link to Abstract: https://www.ncbi.nlm.nih.gov/pubmed/31281177