Self-Monitoring in Management of Hypertension  

Ajay K. Singh, MBBS, FRCP, MBA

Brigham and Women’s Hospital and Harvard Medical School

Boston, Massachusetts

 

One of the most common and problematic issues in the care of patients with chronic kidney disease (CKD) is the control of blood pressure. Hypertension is associated with both progression of CKD and with a higher rate of cardiovascular complications such as stroke and coronary artery disease.

Studies demonstrate that patients with CKD generally have poor blood pressure control. For example, in an analysis of data on 3213 participants from the Fourth National Health and Nutrition Survey, Peralta and colleagues1 reported that more than 60% of patients had inadequate blood pressure control, defined as blood pressure ≥130/80 mmHg.

The emergence in the past decade of affordable self-monitoring devices to measure blood pressure and smartphone software that track blood pressure has allowed for the possibility of practical easy methods for self-monitoring and even self-treatment that did not previously exist. However, prior trials testing the benefits of self-monitoring have led to conflicting results. In a recent PLOS Medicine article2, Tucker and colleagues conclude that self-monitoring of blood pressure on its own does not result in better control of blood pressure, but rather requires additional interventions such as systematic medication titration by clinicians, education, and/or lifestyle counseling. Still, the current American Heart Association guidelines3 recommend “home monitoring for all people with high blood pressure to help the healthcare provider determine whether treatments are working.”

The latest evidence on this issue comes from McManus and colleagues. Their recent study (the TASMINH4 Study) published in Lancet4 is important because they used a randomized control design to test whether self-treatment through self-monitoring of blood pressure could result in greater control of blood pressure. Their trial was a parallel randomized controlled trial conducted in the United Kingdom in 142 general practices. The entry criteria included hypertensive patients >35 years of age and blood pressure >140/90 mm Hg.  Enrolled patients were in their mid-sixties, with a mean body mass index of nearly 30 kg/m2, had a mean blood pressure of 153/86 mm Hg, and 60% had another condition present. A total of 1182 subjects were randomly assigned to either self-monitoring of blood pressure (self-monitoring group), self-monitoring of blood pressure with telemonitoring (telemonitoring group), or usual care using clinic blood pressure (usual care group). The primary outcome was clinic measured systolic blood pressure at 12 months from randomization.

McManus’s trial showed that titration of antihypertensive medication using self-monitoring, with or without telemonitoring, resulted in significantly lower blood pressure (the benefit with telemonitoring was observed after just 6 months, mean reduction of 4.7 mmHg) and with self-monitoring after 1 year (mean reduction of 3.5 mmHg) compared with usual care. There was no significant difference in adverse effects observed. The TASMINH4 study confirms earlier findings reported in Lancet5 by McManus and colleagues (TASMINH2) that showed a mean systolic blood pressure benefit in the self-monitoring and self-treatment group of about 3 mmHg compared with usual care.

While the focus of the McManus study was not on patients with CKD (only 7% of their patients were labeled with the diagnosis of CKD), the findings are likely to be generalizable to all patients with hypertension.

So, what does this all mean? Various devices to measure blood pressure are on the market, including those that allow blood pressure to be imported into a smartphone and then to a physician’s practice. In our patients with CKD where blood pressure management is quite challenging and control of blood pressure is frequently elusive, use of self-monitoring or telemonitoring should be considered an option along with adding more drugs.

 

References

  1. Peralta CA, Hicks LS, Chertow GM, et al. Control of Hypertension in Adults with Chronic Kidney Disease in the United States. Hypertension. 2005;45:1119-1124.
  2. Tucker KL, Sheppard JP, Stevens R, et al. Self-monitoring of blood pressure in hypertension: A systematic review and individual patient data meta-analysis. PLoS Med. 2017 Sep 19;14(9):e1002389. doi: 10.1371/journal.pmed.1002389.
  3. http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/KnowYourNumbers/Monitoring-Your-Blood-Pressure-at-Home_UCM_301874_Article.jsp#.WqaH1mXpYlY Accessed March 12, 2018.
  4. McManus RJ, Mant J, Franssen M, et al. Efficacy of self-monitored blood pressure, with or without telemonitoring, for titration of antihypertensive medication (TASMINH4): an unmasked randomised controlled trial. Lancet. 2018 Feb 27. pii: S0140-6736(18)30309-X. doi: 10.1016/S0140-6736(18)30309-X.
  5. McManus RJ, Mant J, Bray EP, et al Telemonitoring and self-management in the control of hypertension (TASMINH2): a randomized controlled trial. Lancet. 2010 Jul 17;376(9736):163-72. doi:10.1016/S0140-6736(10)60964-6. Epub 2010 Jul 8.