Beta blockers and diuretics are not the best choices for hypertension

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Adapted from Medscape 2 Sept 2022. Hypertension: Real world efficacy of beta blockers versus other anti-hypertensives by Vinod Rane BS Pharm

Patients with hypertension who were treated with ACE inhibitors, Sartans and Calcium Channel blockers such as Amlodipine and Lercanipide had a lower risk of all- cause mortality than those treated with beta blockers.

The risk of all- cause mortality was no different between beta blocker users and those using diuretics.

Cardiovascular mortality was lowest in those treated with ACE inhibitors compared to beta blockers, Sartans, calcium channel blockers and diuretics.

Adapted from Sue Hughes Medscape August 26 2022 TIME: Cardiovascular events similar with evening or morning dose of blood pressure medications.

A five year trial looking at outcomes in those who took their blood pressure medications at night or in the morning showed no difference.

Previous studies have concluded that there could be a benefit to taking anti-hypertensives at night. Dundee researchers headed by Professor Tom MacDonald looked at hard outcomes which included vascular deaths, and non-fatal heart attacks and strokes.

They found “not a smidge of difference” between the two groups.

The study also showed that falls, fractures, or dizzy spells were no more common between the groups. The main thing he said was to take the medications every day at the same time and pick the time that suits you best.

The group tested had an average age of 65, 14% had diabetes,4% smoked,13% had prior CVD and the mean blood pressure at entry was 135/79. The patients were recruited from both primary and secondary care. The duration of follow up was between 5 and 9 years.

My comments: I am aware of the controversies regarding day and night time anti-hypertensives. Some doctors think that blood pressure control is better if drugs are taken at night and some think compliance is better if they are taken in the morning. I take my medication twice a day by splitting the dosage. That way I get good 24 hour coverage and if I forget a dose there is another one coming along in 12 hours or so.

Don’t over treat blood pressure in the over 75s

Adapted from BMJ Oct 10 2020

The lowest mortality in people over the age of 75 occurred in those with a systolic blood pressure of 140-160 and a diastolic pressure of 80-90.

These figures are different than for the middle aged, young retirees and those with diabetes, who are often told to shoot for systolic BPs of 130 to 140.

It was reported Age and Ageing that an analysis of a primary care database that strict blood pressure control can actually be detrimental. Frail older adults do particularly poorly when their blood pressures are too low.

My comment: I remember doing four house calls in a row one warm summer’s day to see older adults, all at different addresses, who had collapsed from over treated blood pressure. None came to serious harm but they could have had fractures, sustained head injuries or collapsed in the street. I have read that a higher blood pressure in older life helps to perfuse the kidneys better. For many patients, they see nurses at nurse led clinics and lower blood pressures are not remarked on. They are told “good, come back in six months or a year”. They only see GPs when the blood pressure is considered to be too high. Instead, patients may be better to have realistic targets set by their GP depending on their age and ongoing health issues and check their blood pressure at home where it is less likely to be artificially raised by anxiety that is common in the health care setting.

Home BP monitors as good as surgery ones

Adapted from Hodgkinson JA et al. Accuracy of blood pressure monitors owned by patients with hypertension (ACCU-RATE study): a cross sectional, observational study in central England. Br J Gen Pract. 2020 June 2

More and more of us are checking our own blood pressure and telling our GPs what the result is over the phone or via skype. Home monitoring has been increasing in the last ten years and has greatly accelerated with the Covid pandemic making avoiding face to face consultations a virtue.

Blood pressure checks are done to diagnose and monitor hypertension but are also a matter of routine for contraceptive pill checks, hormone replacement therapy checks, and diabetes checks.

This study was conducted on just under seven thousand general practice patients in the Midlands of England.

Those who used home blood pressure monitors had them tested against a reference monitor and those who were not within 3 mm Hg were considered to have failed. This is a pretty strict test. The cuffs were also assessed.

In all 76% of the monitors passed on the monitors and cuffs. 86% passed the monitor tests. The monitors that failed mainly tended to over estimate the blood pressure.

In general monitors that have been validated (should say so on the monitor) were more accurate than those that were not. Monitors that cost more than £10 were more accurate than those over £10. Monitors that were under four years old were more accurate than those that were older.

The authors say that BP monitors are very likely to be accurate if they have been validated and are over 4 years old.

UK study shows you can cut BP on a low carb diet by 10 units

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Adapted from Substantial and sustained improvements in blood pressure, weight, and lipid profiles from a carbohydrate restricted diet: an observational study of insulin resistant patients in primary care. David J Unwin. Simon D Tobin et al. Int J Environ Res Public Health 2019 Jul 26;16(15);2680

Hypertension is the second biggest known global risk factor for disease after poor diet. Perhaps lifestyle interventions are underutilised? This study was undertaken in 154 patients with type two diabetes or impaired glucose tolerance in a general practice. This was an observational study that lasted an average of two years.

The average systolic blood pressure reduction was 10.9 mmHg. The mean diastolic reduction was 6.3 mmHg and the mean weight loss was 9.5 Kg. Lipid profiles were markedly improved. Medication was meanwhile reduced by an average of 20%.

Forthcoming Drug Recommendations for Type 2 Diabetics from NICE

NICE have some drug recommendations to make for diabetics in their forthcoming guidelines later this year. It can be seen that NICE are heavily influenced by drug costs. So what could these new guidelines mean for you?

The blood pressure recommendations have scarcely changed but the use of Repaglinide first or second line for blood sugar control is a change from previously. Blood sugar targets have tightened up a bit and structured education is expected for insulin users. Cheaper, older insulins are favoured. Blood sugar testing is being rationed considerably. Aspirin is out of favour but drugs for erectile dysfunction are in. Erythromycin is being adopted for the very difficult to manage problem of gastroparesis.

The medications you will need to take to improve your life with diabetes will depend on many factors. Primarily, what do you want a medication to do for you?

The answer to this will depend on how well you are managing lifestyle changes, how long you have had the condition, the presence of any complications, and how tight you want glycaemic control, blood pressure and lipids to be. The targets need to be individualised to you, and this can be done by becoming more informed about your condition and discussing it with other health care providers and people with diabetes. We discuss these factors in our book, the Diabetes Diet, and I will be updating you on some of the new recommendations in further articles.

This article covers the changes to blood pressure medications, glycaemic targets and drugs to control blood sugar, self-monitoring of blood sugar, insulin initiation and the management of complications.

Blood pressure

For diabetics the BP target is 140/80 if there are no blood vessel complications such as kidney, eye or cerebrovascular disorders. If these are present the target is 130/80. BP lowering can improve peripheral neuropathy as well as stroke, MI, blindness and renal failure. 25% of those with type 2 diabetes develop nephropathy within 20 years of diagnosis.

Because ACE inhibitors and sartans reduce progression to renal disease better than other classes of anti-hypertensive agent they should be used first in diabetics unless they are a woman who could get pregnant as this class of drug is teratogenic. First line for women in this situation is a Calcium channel blocker CCB instead.

For Afro-Caribbean use ACE + diuretic or ACE + Calcium channel blocker. This is because this group respond less well to ACEs and sartans so should have add on drugs right from the start.

For those who can’t tolerate an ACE use a sartan unless there is renal deterioration or hyperkalaemia.

If BP is still not controlled add a CCB or thiazide diuretic.

If still not controlled use any of an alpha blocker e.g. Doxasozin or a beta blocker e.g. Bisoprolol or potassium sparing diuretic e.g. Spironolactone.

If someone has already had a heart attack or heart failure they will probably be on a beta blocker anyway. Carvedilol was superior to metoprolol in metabolic terms for renal protection in one study.

Use spironolactone with caution if someone is already on a sartan or ACE because they all can raise potassium.

Glycaemic control

 

All-cause mortality rises as hbaic rises and decreases as hbaic reduces. The risk of microvascular complications increase over hba1c of 6.5% (48 mmol/mol) or 7% (53) for macrovascular complications. Fasting blood glucose levels influence MI but not stroke or angina.  Amputation rates rise over the age of 60 for any given hbaic. Therefore it can be seen that to improve life expectancy and the quality of life that in general the tighter the blood sugar control the better.  At the same time doctors are asked to adopt an individualised approach to blood sugar targets and consider life expectancy, personal preferences, co-morbidities, risks of polypharmacy and they should consider stopping ineffective drugs.

Targets:

NICE felt they could not comment on hba1c under 6% because only one study they looked at achieved this. Hba1cs in the 4s or 5s are not uncommon in low carbing diabetics however so don’t let this put you off your stride. NICE do say that if adults reach a lower blood sugar target than they were expecting and are not having hypoglycaemia the doctor should encourage them to maintain it.

They suggest:

6.5% for non-drug using diabetics or on drugs that don’t cause hypos e.g. metformin, pioglitazone, gliptins, victoza.

7% for the rest e.g. repaglinide, sulphonylureas, insulin.

7.5% intensify treatment, but individual circumstances e.g. life expectancy, co-morbidities, hypos need to be taken into account.

Drug step-laddering:

The first step for most diabetics is to offer metformin as the initial drug treatment.  But don’t give or stop metformin if the kidney test, the egfr is below 30 and use with caution if under 45. Regular metformin can give diarrhoea and if this is a problem the long acting version can be used.

If there is symptomatic hyperglycaemia, such as thirst and weight loss consider a sulphonylurea or insulin first. Other drugs may be considered once the blood sugars have stabilised. .

Next they suggest Repaglinide on its own or with metformin. Repaglinide is not licenced with other drugs. For people who could not tolerate metformin and repaglinide are the most cost effective treatment option.

If repaglinide was not suitable or is not achieving the desired blood sugar target any of pioglitazone, a sulphonylurea or a gliptin can be used.  The choice can be tailored to the patient.

Sulphonylureas had the most hypos and gliptins the least. Metformin had the best weight loss. Sulphonylurea and Pioglitazone had the most weight gain. NICE prefer doctors to use the lowest cost gliptin because they are relatively expensive.

Reducing hypoglycaemia should be a particular aim for those on insulin or a sulphonylurea. As blood sugar monitoring is necessary for these drugs, this factor can increase the cost considerably over and above the costs of the medication.

Consider GLP1 mimetic i.e. Byetta or Victoza if the BMI is over 35.  Only continue it if hba1c goes down by 1% and weight goes down by 3% over six months.

Insulin is considered to be the “last option”. There is currently research being carried out on the effects of early use of insulin in type two diabetes and this may change practice in the future.

Only offer insulin + Victoza in specialist care setting.

Insulin initiation

When starting insulin use support from an appropriately trained health professional and give:

Structured education

Telephone support

Frequent self monitoring

Dose titration to target

Dietary understanding

Hypoglycaemia management

Management of acute rises in blood sugar

Continue metformin

The usual first choice insulin is NPH insulin at bedtime or twice daily.

The more expensive Lantus or Levemir may be considered if a carer would be able to cut to once daily injections or if hypoglycaemia is a problem or otherwise the patient would need twice daily NPH and oral drugs or they can’t use the NPH device.

If hbaic is 9% (75) consider twice daily pre-mixed bi-phasic insulin.

Blood sugar testing

NICE recommends that self- monitoring of blood sugars is to be avoided unless a person is on insulin, has symptomatic hypoglycaemia, or oral medication that causes hypos or driving or operating machinery, pregnant or trying for a baby.  It may be worth considering if a patient is on oral or intravenous steroids.

Doctors or nurses should reassess the need for self monitoring annually to see if it remains worthwhile.

Self monitoring produced only a 0.22% reduction in hbaic. It was considered by NICE to be not helpful for most people with type two diabetes though more hypos were detected with it.

 

Anti-platelet therapy for cardiovascular protection

There is no overall benefit to taking aspirin or clopidogrel in type 2 diabetes unless they already have cardiovascular disease.

Managing complications

Autonomic neuropathy symptoms are: gastroparesis, diarrhoea, faecal incontinence, erectile dysfunction, bladder disturbance, orthostatic hypotension, gustatory and other sweating disorders, dry feet and ankle oedema.

Treatments for gastroparesis are metoclopramide, domperidone and erythromycin.

Refer to a specialist if severe or persistent vomiting occurs or the diagnosis is in doubt.

Nocturnal diarrhoea may indicate autonomic neuropathy.

Tricyclics are often given for neuropathic pain but can increase postural hypotension.

Erectile dysfunction

Offer men the chance to speak about this at their annual review. Offer Viagra, Cialis and similar and refer if these don’t work.

Eye damage

Diabetic eye damage is the single largest cause of blindness before old age.

Refer to the emergency ophthalmologist if:

Sudden loss of vision

Rubeus’s Iridis

Pre-retinal or vitreous haemorrhage

Retinal detachment

Send for rapid review if there is new vessel formation.

So what do you think of the new NICE recommendations?  Do you think these changes will affect your medications?