Saturday, August 6, 2016

Clinical examination nowadays

I am a retired physician and teacher. I studied medicine and taught it with a strong emphasis on taking the history of patients and physical examination before diagnosis. I have told my students that in more than half of patients, the history is the main determinant of the diagnosis. With the gradual shift of emphasis towards technology, I now see doctors facing the patient with a laptop in front of them, asking few questions then, with a limited or no physical examination, handing the patient a long list of tests to be done in the laboratory and various imaging facilities. I realise that the information obtained from properly chosen laboratory and imaging tests can be more accurate and more objective than information obtained through interrogation and physical examination. But, the proper choice of tests depends on a good differential diagnosis based on a good history and physical examination. Irrelevant tests are a waste of time and money, place an unnecessary burden on the patient, are a possible cause of side-effects that can sometimes be serious, and a cause of delay to other patients who actually need these tests. Moreover, interpretation of the test results depends on the probability of the condition you are testing for. The predictive value of a test varies with the pre-test probability of the disease, which in turn depends on the information obtained from the history and physical examination.
Moreover, careful questioning and examination strengthens the doctor–patient relationship, builds a patient's confidence in their doctor, and makes them feel that their doctor cares. The importance of doctor–patient communication for a person whose life and wellbeing depend on this relationship cannot be overemphasised.
I declare no competing interests.

Sunday, December 20, 2015

Hypertension treatment. What is the target?

The recent publication(1) of the results of SPRINT (Systolic Blood Pressure Intervention Trial) was received as an important news. It showed that lowering systolic blood pressure in hypertensive patients to a target of less than 120 mm. Hg. produced better results than the generally recommended target of less than 140 mm. Hg.

(More than 9000 patients who were hypertensive and not diabetic, were randomized into 2 groups: one treated to a target systolic pressure of less than 140 mm. Hg. and the other to a target of less than 120 mm. Hg. After about 3 years, the lower target group had a 25% lower relative risk of the primary composite end point of myocardial infarction, acute coronary syndrome, stroke, acute heart failure, and cardiovascular death. In addition, the lower target group had 27% lower risk of all-cause mortality. However, this group also had higher adverse events such as hypotension, syncope, and acute kidney injury or failure. The trial was stopped by the safety monitoring board before completing its planned 5 year period when the difference between the two groups became obvious.)

Interestingly this represented a move in the opposite direction to the last hypertension guidelines of the Joint National Committee (JNC 8)(2) published early 2014, which suggested that the target systolic pressure can be relaxed in people 60 y. old and above to 150 mm. Hg.; a suggestion received with scepticism by many at the time.

Blood pressure is a continuous characteristic in the community with a unimodal distribution curve. There is no clear separation between hypertensive and normotensive people.

(This point was the subject of a well known debate in the forties and fifties of the last century between two British physicians, George W. Pickering who held the idea of a unimodal distribution and thought that primary hypertension represents the pressure of people on the high side of the distribution curve and Robert Plat who claimed that the distribution is bimodal and that primary hypertension is a separate disease entity carried by an autosomal dominant gene. Pickering idea prevailed. It conforms with the present thinking.)

The complications of high blood pressure are the results of the physical effects of blood pressure on the arterial wall and the heart and as such are proportional to the height of blood pressure (correlating more with systolic pressure). They constitute a continuum without cut off points above which complications occur and below which they do not. The lower the pressure, the less are the possible complications. On the other hand lower pressure may impair tissue perfusion and may predispose to thrombosis. The optimum level is that which produces the most benefit and least risk. If going down to 120 mm. Hg. produces a better risk benefit balance then it will be reasonable to make it the target. But one would like this to be confirmed by further studies. The other important point is that every patient is unique and advices based on studies of groups of patients do not necessarily apply to every individual patient. You will have to decide in each patient whether the advantages of further lowering of systolic pressure outweigh the possible risks.
(1) The SPRINT Research Group; A Randomized Trial of Intensive versus Standard Blood Pressure Control; N Engl J Med 2015; 373; 2103-2116.

(2) Report from the panel members appointed to the Eighth Joint National Committee (JNC 8); 2014 Evidence Based Guideline for the Management of High Blood Pressure in Adults; JAMA 2014; 311(5):507-520.

Thursday, February 12, 2015

مساعدة أم فضول؟

مساعدة الاخرين شيء جميل وفضيلة محمودة.
ترى شخصا يحاول عملا أو أنجاز مهمة. تقدر ان الامر يصعب على شخص واحد فتعرض المساعدة. يقبلها شاكرا فتعينه في تحقيق ما يريد بالصورة التي يريدها أو تقترح بديلا فيستحسنه وتعينه عليه. يشكرك وتمضي في سبيلك مرتاح الضمير. صورة جميلة لما ينبغي ان يكون.
ولكن هل هي دائما كذلك؟
هناك صورة اخرى.
ترى شخصا يحاول عملا أو أنجاز مهمة. تقدر ان دخولك في الامر مطلوب. تذهب وتساهم في العمل دون اذن. يشكرك ويقول بادب ان الامر سهل عليه ولا يستدعي المساعدة ولكنك لا تأبه بما يقول وتمضي في العمل حسب ما ترتئيه أنت. يعترض بلطف ويبين انه يريد ان ينجز العمل بالصورة التي يرتئيها ولكنك تصر انك تعرف اكثر منه. يتحملك على مضض ويتمنى في قرارة نفسه ان يتخلص من هذه المساعدة!
هناك خط يفصل بين المساعدة وبين التدخل في شؤون الاخرين. ولكن بعض الناس لا يرى هذا الخط!

Tuesday, September 9, 2014

PSA screening: A public health disaster?!

  1. A friend of mine had an elevated PSA (Prostate Specific Antigen) level some years ago. He was naturally worried. He had some prostatic symptoms, so he underwent a transurethral resection of prostate which was found to be negative for cancer. Another friend also had an elevated PSA. After few years of worry and repeated tests he had a needle biopsy of the prostate which was negative. He decided not to do the test again. A third friend, a pathologist, also had an elevated PSA and decided to ignore it. He said too many prostates had been removed unnecessarily because of the test, sometimes with tragic consequences like incontinence and impotence.
  2. Dr. Richard Ablin, who discovered the prostate specific antigen in 1970, recently published a book about it titled "The great prostate hoax"(1). In the book and prior to that in an article in the New York Times(2) he described screening for prostate cancer using PSA as a "public health disaster"!
  3. In a thought provoking interview with Dr. Ablin on Medscape on  August 8, 2014(3) he told the story of the test, a story that makes one scratch his head:
    1. In 1970 he, an immunologist, was working with two urologists studying freezing prostates (cryosurgery) as a treatment of prostate cancer. They noticed that cryosurgery in animals induced an immune response which increased when freezing was repeated. They also noticed that in some patients with metastasizing prostate cancer who underwent cryosurgery of prostate, metastasis were reduced in size which may have been, they thought, due to antibodies induced by the surgery. Dr. Albin could then isolate the antigen responsible for the immune response. He thought first it was a cancer specific antigen but later realized it was a tissue specific antigen (i.e. prostate specific) and not cancer specific because it was also present in normal prostate tissue and in benign prostatic hypertrophy. He also noticed that in cancer patients its concentration decreased with treatment and increased again with recurrence which makes it suitable for following patients and detecting recurrence. In 1986 the test was approved by the FDA (Food and Drug Administration) as a harbinger of recurrence.
    2. In 1989, Schering-Plough Company paid $1.2 million to a marketing firm to promote PSA screening in asymptomatic men to detect prostate cancer. Primary care physicians were brainwashed that they needed to order PSA tests for patients. Many doctors started to use the test, off label, for detecting prostate cancer!
    3. In 1994 it was approved by the FDA as a test to detect cancer in spite of the fact that it was pointed out to the group discussing its approval that the test has a false positive rate of 78% i.e. it is wrong in nearly 80% of the time!!
    4. The latest statistics show that the annual budget for the National Cancer Institute (of the USA) is about $5.1 billion; of that, approximately $300 million goes for urologic research. Compared to this, every year $3 billion are spent, in the United States on PSA screening in asymptomatic men!(3)

  1. Ablin RJ, Piana R. The Great Prostate Hoax: How Big Medicine Hijacked the PSA Test and Caused a Public Health Disaster. New York: Macmillan Publishers; 2014.

Monday, August 25, 2014

The side room laboratory

 When I was a final year medical student, many years ago, we used to have a side room laboratory in every medical ward. It was the job of the final year student to do the simple laboratory tests needed by the patients like urinalysis, stool exam, blood counts etc. We used to spend a considerable time in that laboratory which also served as our meeting place to discuss medical issues and also chat about various subjects. When I became a resident doctor I also used to spend a significant time during afternoons and nights in the side room laboratory doing simple tests that were needed by newly admitted patients. That was part of the job of the resident doctor. Even in my membership examination in London, when I was given my long case I was shown the side room laboratory and asked to do, if I want to, whatever test I thought useful in reaching a diagnosis. When I was training in kidney disease, they used to say: a good nephrologist is one who looks at the urine himself.
Things gradually changed. By the time I was on the teaching staff, medical students were relieved from this duty although some hospitals retained a simple side room laboratory used by the occasional keen student or resident. These also gradually disappeared. All tests came to be sent to the general laboratory of the hospital.

Was that a change for the better?
If you are working in a place where a reliable laboratory is available and easy to reach all the time, then clinicians probably do not need to involve themselves in doing laboratory tests. That will save them more time to spend with their patients. Laboratory people are also more skilled and experienced in laboratory work and their results should be more reliable.
But, do all clinicians work in such convenient circumstances?
Many do not, especially in less developed countries. For these, some simple laboratory tests done on the patient's bedside or in a small side room laboratory can be immensely useful. Examining the urine can be done in minutes in the presence of dipsticks that test for various chemicals like protein, sugar, ketones, hemoglobin, bilirubin, urinobilingen etc. Vital information about the state of the urinary system and the whole body can then be obtained. Looking at a urine drop under the microscope searching for various cells gives important information about the urinary system. Seeing bacteria swimming in that drop may be more reliable in diagnosing urinary infection  than a urine culture done by a laboratory of a questionable quality. It also gives a rough idea about the number of bacteria (knowing that one bacterium in a high power field corresponds roughly to 30,000 bacteria in a milliliter of the urine sample). Looking at a drop of cerebrospinal fluid under the microscope in the middle of the night when the hospital laboratory is not open yet, can be sufficient to start treatment of meningitis and probably save life. Many more examples can be cited.

Clinicians' performance of simple laboratory tests still has a place in medical practice and medical education especially in less developed countries.

Wednesday, August 20, 2014

نقاش بلا صراع

ما الهدف من الدخول في نقاش؟
الهدف الامثل هو تبادل الرأي للوصول الى الحقيقة او الى افضل الطرق لحل مشكلة او خلاف. في احيان اخرى يكون الهدف هو الترويج لراي واثبات انه الراي الصحيح وان الراي الاخر خطأ وهو ما نراه في المناقشات التي تجرى في وسائل الاعلام في السياسة على وجه الخصوص ولا يكون الامر تبادلا للرأي وانما صراع يسعى كل طرف ان يكون الفائز فيه. ما يعنيني هنا هو النوع الاول الذي يبدؤه المتناقشون بقصد تبادل الراي والوصول الى الحقيقة ولكنه قد يتحول الى صراع يطلب فيه كل طرف الفوز على الطرف الثاني.  كل طرف له رأي مسبق يصبح هدفه الدفاع عنه وليس الوصول الى الحقيقة. سلاحه في ذلك الكلام ولذا يحاول ان يتكلم اكثر الوقت وكثيرا ما نرى المتناقشين كلهم يتكلمون ولا احد يستمع واذا اضطر الى الاستماع فانما يستمع ليرد وليس ليفهم  (على حد قول الكاتب الامريكي ستيفن كوفي) وكثيرا ما تدخل العاطفة والحماس وتطغى على الفكر والتدبر. تختلف قوة عنصر الصراع باختلاف مستوى المتناقشين وتقل كلما زادت ثقافتهم وتحضرهم ونضجهم الفكري.

ان نجاح النقاش يعتمد الى حد كبير على نزع عنصر الصراع منه. وذلك باحترام راي الطرف المقابل وتجنب وصمه بالخطأ وابداء الراي بهدوء وتواضع وعدم الالحاح في الجدل منتظرا ان يرفع الطرف الاخر الراية البيضاء ويسلم بانك على حق فانك حتى لو كنت فعلا على حق فان تغيير الراي كثيرا ما يحتاج الى وقت فاترك المقابل ليتمعن مع نفسه في ما قلت له. واذا لم تتوصلوا الى اتفاق ثم حدث ما يدلل على انك كنت على حق فلا تظهر بمظهر المنتصر المنتشي بانتصاره وتذكره بما قلت له فان مثل هذا قد يدفعه على الاصرار على رأيه حتى مع اقتناعه بخطئه حفاظا على كرامته.

Saturday, July 5, 2014

Using guidelines? Think carefully

  1. Guidelines are meant to help the doctor deal with an individual patient but they are based on information obtained from groups of patients. Description of groups has to rely on statistics using averages to describe various characteristics and results.
  2. When you apply the results of various medical interventions obtained in a group (frequently in the thousands) to your individual patient, you are presuming that your patient is similar to the patients in the group so that you expect him to respond to the treatment in a similar way to that of the group. But the response of different patients in the group is not the same. You do not know the characteristics of various individuals in the group and how each one responded. What you may know is the averages of their characteristics and the averages of their responses. Those who wrote the guidelines for you based their guidelines on these.
  3. The critical question then is whether your patient is sufficiently similar to the average of the group (or the groups) studied so that you can reasonably apply the guidelines to him.
  4. This can best be explained by an example. Guidelines on the treatment of non valvular atrial fibrillation using CHAD or CHADS2 score lump together patients with permanent atrial fibrillation and patients with paroxysmal atrial fibrillation. Treating the two types similarly is based on studies that showed similar prognosis regarding their liability to develop strokes. The cause of this is not clear but it may be related to the fact that the patient with paroxysmal fibrillation is more prone to develop a stroke  when fibrillation reverts to sinus rhythm and this may offset his decreased risk when he is in sinus rhythm. The vital question is this: are we justified to treat a patient who has two or three attacks a year each lasting several minutes in the same way as a patient who has daily (or every few days) attacks each lasting many hours because both patients carry the same label of paroxysmal fibrillation?!
  5. Applying guidelines to your patient without considering his individual characteristics and circumstances is like a tailor who, when asked to make a suit for an Iraqi man, does not take his measures; instead he makes the suit relying on statistical figures describing the physical characteristics of Iraqi men. If the man happened to be much taller (or shorter) than the average Iraqi, it is just bad luck!
  6. This does not mean that we should not use guidelines but that we should take into consideration the individual characteristics and circumstances of the patient we are treating. You should ask yourself whether your patient is sufficiently similar to the average patient with that condition to justify applying the guidelines in his case. If not, you should modify your application of the guidelines according to your judgment of the magnitude of the difference.